introspection: include gstversion.h in GIR generation
introspection: include gstversion.h in GIR generation

https://bugzilla.gnome.org/show_bug.cgi?id=703021

shelsonjava/gstreamer,shelsonjava/gstreamer,jpxiong/gstreamer,StreamUtils/gstreamer,StreamUtils/gstreamer,jpxiong/gstreamer,surround-io/gstreamer,shelsonjava/gstreamer,StreamUtils/gstreamer,mparis/gstreamer,mparis/gstreamer,krichter722/gstreamer,surround-io/gstreamer,jpakkane/gstreamer,jpakkane/gstreamer,krichter722/gstreamer,shelsonjava/gstreamer,StreamUtils/gstreamer,surround-io/gstreamer,centricular/gstreamer,Lachann/gstreamer,Lachann/gstreamer,jpakkane/gstreamer,jpakkane/gstreamer,Lachann/gstreamer,Lachann/gstreamer,mparis/gstreamer,jpakkane/gstreamer,StreamUtils/gstreamer,centricular/gstreamer,jpxiong/gstreamer,krichter722/gstreamer,jpxiong/gstreamer,krichter722/gstreamer,centricular/gstreamer,centricular/gstreamer,jpxiong/gstreamer,shelsonjava/gstreamer,surround-io/gstreamer,centricular/gstreamer,krichter722/gstreamer,mparis/gstreamer,mparis/gstreamer,Lachann/gstreamer,surround-io/gstreamer