Release: increased version to 1.2.4

	* configure.ac: changed version of required gstreamer version
	  to 1.2.4 and version of gstreamermm to 1.2.4 too
Release: regenerated *.defs files according to gstreamer 1.2.4 version

I decided to remove patches content, to avoid rubbish (unnecessary entries)
in a code.

	* gstreamer/gstreamermm.h:
	* gstreamer/src/filelist.am: temporary disabled audioresample
	  plugin. It can be enabled after wrapping enum
	  SpeexResamplerSincFilterMode. Probably audioresample.{hg|ccg}
	  cannot be generated.
	* gstreamer/src/gst_docs.xml: regenerated documentation files
	* gstreamer/src/gst_enums.defs:
	* gstreamer/src/gst_methods.defs:
	* gstreamer/src/gst_signals.defs: regnerated enum, methods and
	  signals defs file
	* gstreamer/src/gst_enums.defs.patch:
	* gstreamer/src/gst_methods.defs.patch:
	* gstreamer/src/gst_signals.defs.patch: some autogenerated defs
	  are incorrect, so we have to apply some patches after
	  regeneration.
Plugins: enabled elements plugins from gst-plugins-base package:
    - multisocketsink
    - input-selector
    - output-selector.
There is still one disabled element: audioresample.

     * .gitignore: added multisocketsink generated files to ignored
	  list. The rest of added plugins were already there.
	* configure.ac: added plugins to .hg|.ccg generation list
	* gstreamer/src/filelist.am: added .hg files of added plugins to
	  a further generator list
	* gstreamer/src/gst_enums.defs: applied a patch described below
	* gstreamer/src/gst_enums.defs.patch:  added define of missing
	  enums from multisocketsink element, which cannot be
	  autogenerated
	* tools/m4/convert_gst.m4: added conversion rule from Gio::Socket
	  refptr to GSocket*
	* tools/m4/plugingen_gstreamermm.m4: added translation entry of
	  GSocket* and GObject*