Remeber, win32 has a socket type that's actually a handle, so if
there's a chance that code is run on win32, we can't use "int" as the
socket type.
This isn't a blind search-and-replace: sometimes an fd is really in
fact for a file, and not a socket at all.
This is a bit of an interface doozy, but it's really needed in order
to be able to document this stuff without apologizing it. This patch
does the following renamings:
evbuffercb -> bufferevent_data_cb
everrorcb -> bufferevent_event_cb
EVBUFFER_(READ,WRITE,...) -> BEV_EVENT_(...)
EVBUFFER_(INPUT,OUTPUT) -> bufferevent_get_(input,output)
All the old names are available in event2/bufferevent_compat.h
svn:r1283
