Merge commit 'origin/plugins' into plug-in

configure.ac

sflphone-gtk/configure.ac

sflphone-gtk/src/dbus.c

sflphone-gtk/src/menus.c

src/Makefile.am

src/audio/alsalayer.cpp

src/audio/audiortp.cpp

src/audio/pulselayer.cpp

src/managerimpl.cpp

src/managerimpl.h

src/sipvoiplink.cpp

src/useragent.cpp