Add JoinAfterCloaked setting to q.cpp
Add JoinAfterCloaked setting to q.cpp

This patch adds a new setting to the Q module, JoinAfterCloaked, that
allows the user to specify whether ZNC should postpone joining channels
before the user is cloaked.

Fixes #286

withinsoft/znc,withinsoft/znc,withinsoft/znc,withinsoft/znc,withinsoft/znc,withinsoft/znc