- make clients cache directories and use them to seed their router lists
   at startup.  This means clients have a datadir again.
 - Introduce a global_write_bucket.  We need to respond better to exhausting
   it.
 - Remove the last vestiges of LinkPadding and TrafficShaping.
 - Configuration infrastructure support for warning on obsolete options.
 - Refactor directory header parsing to use smartlist_split_string.
 - Respond to content-encoding headers by trying to uncompress as appropriate.
 - Reply with a deflated directory when a client asks for "dir.z".
   (We could use allow-encodings instead, but allow-encodings isn't
   specified in HTTP 1.0.)


svn:r2335