Add stub directory-level documentation for most source directories

This includes app, core, feature, lib, and tools, but excludes
ext, test, and trunnel.

This was generated by the following shell script:

cd src
for dname in $(find lib core feature app tools -type d |grep -v \\.deps$); do
    keyword="$(echo "$dname" |sed -e "s/\//_/" )"
    target="${dname}/${keyword}.dox"
    echo "$target"
    cat <<EOF >"$target"
/**
@dir ${dname}
@brief ${dname}
**/
EOF

    git add "$target"
done

src/app/app.dox

@@ -0,0 +1,4 @@
+/**
+@dir app
+@brief app
+**/

src/app/config/app_config.dox

@@ -0,0 +1,4 @@
+/**
+@dir app/config
+@brief app/config
+**/

src/app/main/app_main.dox

@@ -0,0 +1,4 @@
+/**
+@dir app/main
+@brief app/main
+**/

src/core/core.dox

@@ -0,0 +1,4 @@
+/**
+@dir core
+@brief core
+**/

src/core/crypto/core_crypto.dox

@@ -0,0 +1,4 @@
+/**
+@dir core/crypto
+@brief core/crypto
+**/

src/core/mainloop/core_mainloop.dox

@@ -0,0 +1,4 @@
+/**
+@dir core/mainloop
+@brief core/mainloop
+**/

src/core/or/core_or.dox

@@ -0,0 +1,4 @@
+/**
+@dir core/or
+@brief core/or
+**/

src/core/proto/core_proto.dox

@@ -0,0 +1,4 @@
+/**
+@dir core/proto
+@brief core/proto
+**/

src/feature/api/feature_api.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/api
+@brief feature/api
+**/

src/feature/client/feature_client.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/client
+@brief feature/client
+**/

src/feature/control/feature_control.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/control
+@brief feature/control
+**/

src/feature/dirauth/feature_dirauth.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/dirauth
+@brief feature/dirauth
+**/

src/feature/dircache/feature_dircache.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/dircache
+@brief feature/dircache
+**/

src/feature/dirclient/feature_dirclient.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/dirclient
+@brief feature/dirclient
+**/

src/feature/dircommon/feature_dircommon.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/dircommon
+@brief feature/dircommon
+**/

src/feature/dirparse/feature_dirparse.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/dirparse
+@brief feature/dirparse
+**/

src/feature/feature.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature
+@brief feature
+**/

src/feature/hibernate/feature_hibernate.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/hibernate
+@brief feature/hibernate
+**/

src/feature/hs/feature_hs.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/hs
+@brief feature/hs
+**/

src/feature/hs_common/feature_hs_common.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/hs_common
+@brief feature/hs_common
+**/

src/feature/keymgt/feature_keymgt.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/keymgt
+@brief feature/keymgt
+**/

src/feature/nodelist/feature_nodelist.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/nodelist
+@brief feature/nodelist
+**/

src/feature/relay/feature_relay.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/relay
+@brief feature/relay
+**/

src/feature/rend/feature_rend.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/rend
+@brief feature/rend
+**/

src/feature/stats/feature_stats.dox

@@ -0,0 +1,4 @@
+/**
+@dir feature/stats
+@brief feature/stats
+**/

src/lib/arch/lib_arch.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/arch
+@brief lib/arch
+**/

src/lib/buf/lib_buf.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/buf
+@brief lib/buf
+**/

src/lib/cc/lib_cc.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/cc
+@brief lib/cc
+**/

src/lib/compress/lib_compress.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/compress
+@brief lib/compress
+**/

src/lib/conf/lib_conf.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/conf
+@brief lib/conf
+**/

src/lib/confmgt/lib_confmgt.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/confmgt
+@brief lib/confmgt
+**/

src/lib/container/lib_container.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/container
+@brief lib/container
+**/

src/lib/crypt_ops/lib_crypt_ops.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/crypt_ops
+@brief lib/crypt_ops
+**/

src/lib/ctime/lib_ctime.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/ctime
+@brief lib/ctime
+**/

src/lib/defs/lib_defs.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/defs
+@brief lib/defs
+**/

src/lib/dispatch/lib_dispatch.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/dispatch
+@brief lib/dispatch
+**/

src/lib/encoding/lib_encoding.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/encoding
+@brief lib/encoding
+**/

src/lib/err/lib_err.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/err
+@brief lib/err
+**/

src/lib/evloop/lib_evloop.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/evloop
+@brief lib/evloop
+**/

src/lib/fdio/lib_fdio.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/fdio
+@brief lib/fdio
+**/

src/lib/fs/lib_fs.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/fs
+@brief lib/fs
+**/

src/lib/geoip/lib_geoip.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/geoip
+@brief lib/geoip
+**/

src/lib/intmath/lib_intmath.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/intmath
+@brief lib/intmath
+**/

src/lib/lib.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib
+@brief lib
+**/

src/lib/lock/lib_lock.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/lock
+@brief lib/lock
+**/

src/lib/log/lib_log.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/log
+@brief lib/log
+**/

src/lib/malloc/lib_malloc.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/malloc
+@brief lib/malloc
+**/

src/lib/math/lib_math.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/math
+@brief lib/math
+**/

src/lib/memarea/lib_memarea.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/memarea
+@brief lib/memarea
+**/

src/lib/meminfo/lib_meminfo.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/meminfo
+@brief lib/meminfo
+**/

src/lib/net/lib_net.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/net
+@brief lib/net
+**/

src/lib/osinfo/lib_osinfo.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/osinfo
+@brief lib/osinfo
+**/

src/lib/process/lib_process.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/process
+@brief lib/process
+**/

src/lib/pubsub/lib_pubsub.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/pubsub
+@brief lib/pubsub
+**/

src/lib/sandbox/lib_sandbox.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/sandbox
+@brief lib/sandbox
+**/

src/lib/smartlist_core/lib_smartlist_core.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/smartlist_core
+@brief lib/smartlist_core
+**/

src/lib/stats/lib_stats.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/stats
+@brief lib/stats
+**/

src/lib/string/lib_string.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/string
+@brief lib/string
+**/

src/lib/subsys/lib_subsys.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/subsys
+@brief lib/subsys
+**/

src/lib/term/lib_term.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/term
+@brief lib/term
+**/

src/lib/testsupport/lib_testsupport.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/testsupport
+@brief lib/testsupport
+**/

src/lib/thread/lib_thread.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/thread
+@brief lib/thread
+**/

src/lib/time/lib_time.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/time
+@brief lib/time
+**/

src/lib/tls/lib_tls.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/tls
+@brief lib/tls
+**/

src/lib/trace/lib_trace.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/trace
+@brief lib/trace
+**/

src/lib/version/lib_version.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/version
+@brief lib/version
+**/

src/lib/wallclock/lib_wallclock.dox

@@ -0,0 +1,4 @@
+/**
+@dir lib/wallclock
+@brief lib/wallclock
+**/

src/tools/tools.dox

@@ -0,0 +1,4 @@
+/**
+@dir tools
+@brief tools
+**/