On the serf-195 branch: Reorganize and rename the reqest list functions.

* serf_private.h
  (serf_reqlist_t): Add docstring.
  (serf__reqlist_push): Renamed from serf__push_request.
  (serf__reqlist_peek): Renamed from serf__peek_request.
  (serf__reqlist_pop): Renamed from serf__take_request.
  (serf__reqlist_delete): Renamed from serf__delete_from_reqlist.
  (serf__reqlist_recalc): Renamed from serf__req_list_recalc_length.

* protocols/http2_stream.c,
  src/outgoing.c,
  src/outgoing_request.c: Updated all references.

* src/outgoing_request.c:
  (serf__reqlist_push, serf__reqlist_peek, serf__reqlist_pop,
   serf__reqlist_delete, serf__reqlist_recalc): Moved implementations
   to the top of the file.


git-svn-id: https://svn.apache.org/repos/asf/serf/branches/SERF-195@1935100 13f79535-47bb-0310-9956-ffa450edef68