Processing of gzip encoded incoming requests (on /yacy/transferRWI.html
and /yacy/transferURL.html) was no more working since upgrade to Jetty
9.4.12 (see commit 51f4be1).
To prevent any conflicting behavior with Jetty internals, use now the
GzipHandler provided by Jetty to decompress incoming gzip encoded
requests rather than the previously used custom GZIPRequestWrapper.
Fixes issue #249