Accept hs descriptors even if we don't see an HSDir for us

The old behavior contributed to unreliability when hidden services and
hsdirs had different consensus versions, and so had different opinions
about who should be cacheing hsdir info.

Bugfix on 0.2.0.10-alpha; based on discussions surrounding bug 2732.

src/or/routerlist.c

@@ -5778,11 +5778,6 @@ hid_serv_acting_as_directory(void)
              "being a hidden service directory.");
     return 0;
   }
-  if (!rs->is_hs_dir) {
-    log_info(LD_REND, "We're not listed as a hidden service directory in "
-             "the consensus, so we won't be one.");
-    return 0;
-  }
   return 1;
 }