src.pro: allow specifying COMMUNI_BUILDDIR
communi.pri: do not use frameworks in static builds
Task #57: Docs: cleanup brief descriptions
Fix #55: irc.h: cleanup obsolete Q_ENUMS(Message)
IrcProtocol: fix memory leak
Docs: add missing IrcMessage::Motd/Names enum values
src.pri: enable QtNetwork for convenience
Changelog for 2.1.1