Split most of dirserv.c into several new modules

In dirauth:
  * bwauth.c reads and uses bandwidth files
  * guardfraction.c reads and uses the guardfraction file
  * reachability.c tests relay reachability
  * recommend_pkg.c handles the recommended-packages lines.
  * recv_descs.c handles fingerprint files and processing incoming
    routerinfos that relays upload to us
  * voteflag.c computes flag thresholds and sets those thresholds on
    routerstatuses when computing votes

In control:
  * fmt_serverstatus.c generates the ancient "v1 server status"
    format that controllers expect.

In nodelist:
  * routerstatus_fmt.c formats routerstatus entries for a consensus,
    a vote, or for the controller.

src/core/mainloop/main.c

@@ -74,6 +74,9 @@
 #include "lib/crypt_ops/crypto_rand.h"
 #include "feature/dircache/directory.h"
 #include "feature/dircache/dirserv.h"
+#include "feature/dirauth/bwauth.h"
+#include "feature/dirauth/reachability.h"
+#include "feature/dirauth/process_descs.h"
 #include "feature/relay/dns.h"
 #include "feature/client/dnsserv.h"
 #include "core/or/dos.h"
@@ -3663,7 +3666,9 @@ tor_free_all(int postfork)
   routerlist_free_all();
   networkstatus_free_all();
   addressmap_free_all();
+  dirserv_free_fingerprint_list();
   dirserv_free_all();
+  dirserv_clear_measured_bw_cache();
   rend_cache_free_all();
   rend_service_authorization_free_all();
   rep_hist_free_all();