More fractional framerate conversions

More fractional framerate conversions

Original commit message from CVS:
* ext/cairo/gsttextoverlay.c: (gst_text_overlay_init),
(gst_text_overlay_setcaps), (gst_text_overlay_collected):
* ext/cairo/gsttextoverlay.h:
* ext/gdk_pixbuf/gstgdkpixbuf.c: (gst_gdk_pixbuf_sink_link):
* ext/gdk_pixbuf/gstgdkpixbuf.h:
* ext/libpng/gstpngdec.c: (gst_pngdec_init),
(gst_pngdec_caps_create_and_set):
* ext/libpng/gstpngdec.h:
* ext/libpng/gstpngenc.c: (gst_pngenc_setcaps):
* gst/alpha/gstalphacolor.c: (gst_alpha_color_set_caps):
* gst/avi/gstavimux.c: (gst_avimux_init),
(gst_avimux_vidsinkconnect):
* gst/flx/gstflxdec.c: (gst_flxdec_chain):
* gst/goom/gstgoom.c: (gst_goom_init), (gst_goom_src_setcaps),
(gst_goom_src_negotiate), (gst_goom_chain):
* gst/goom/gstgoom.h:
* gst/matroska/matroska-demux.c: (gst_matroska_demux_video_caps):
* gst/matroska/matroska-mux.c:
(gst_matroska_mux_video_pad_setcaps):
* sys/osxvideo/osxvideosink.h:
* sys/osxvideo/osxvideosink.m:
More fractional framerate conversions