QTimers were used to queue incoming daemon signals on LRC eventloop.

Problem, this workaround caused issues on Win and OSX since the daemon
could emit signals on internal threads, preventing QTimers to start
(they need a QThread to run). Therefore, some signals were never
relayed.
We now use a QueuedConnection when connecting to these callbacks. It
takes care of queing incoming signals on the eventloop.

Change-Id: I2bd8a12913ded14ee1c9d1af33a51f43c22d2b96
Tuleap: #1133