X C Bindings video output proof of concept plugin

This can really only output iamges at this point.
Critical yet-to-be-implemented features:
 - MIT-SHM shared memory support
 - XVideo hardware scaling & chroma conversion
 - keyboard event handling
 - mouse event handling
 - window (manager) event handling
 - cursor blanking
 - window provider submodule (so it can work without the Qt interface)
 - screen capture access module
 - GLX, perhaps?
 - etc

15, 16 and 24-bits color depth work. 32-bits depth was not tested due
to lack of suitable video adapter. 8-bits depth does not work due to a
bug in VLC chroma handling. B&W, grey and 16 color are not supported,
but are probably not worth it - the Xlib output does not support them
either.

Fullscreen should work, but was not tested.

modules/video_output/Modules.am

@@ -20,4 +20,15 @@ SOURCES_directfb = directfb.c
 SOURCES_vmem = vmem.c
 SOURCES_yuv = yuv.c
 
+# TODO: move to configure.ac once/if xcb plugin gets more functional
+XCB_LIBS = -lxcb
+XCB_AUX_LIBS = -lxcb-aux
+XCB_IMAGE_LIBS = -lxcb-image
 
+libxcb_plugin_la_SOURCES = xcb/xcb.c
+libxcb_plugin_la_CFLAGS = $(AM_CFLAGS) \
+	$(XCB_CFLAGS) $(XCB_AUX_CFLAGS) $(XCB_IMAGE_CFLAGS)
+libxcb_plugin_la_LIBADD = $(AM_LIBADD) \
+	$(XCB_LIBS) $(XCB_AUX_LIBS) $(XCB_IMAGE_LIBS)
+libxcb_plugin_la_DEPENDENCIES =
+EXTRA_LTLIBRARIES += libxcb_plugin.la