Port pango-based textoverlay, timeoverlay and textrender to 0.9 and add background...

Port pango-based textoverlay, timeoverlay and textrender to 0.9 and add background shading and text wrapping modes. M...

Original commit message from CVS:
* configure.ac:
* ext/Makefile.am:
* ext/pango/Makefile.am:
* ext/pango/gstclockoverlay.c: (gst_clock_overlay_base_init),
(gst_clock_overlay_render_time), (gst_clock_overlay_get_text),
(gst_clock_overlay_class_init), (gst_clock_overlay_init):
* ext/pango/gstclockoverlay.h:
* ext/pango/gsttextoverlay.c: (gst_text_overlay_base_init),
(gst_text_overlay_get_text), (gst_text_overlay_class_init),
(gst_text_overlay_finalize), (gst_text_overlay_init),
(gst_text_overlay_update_wrap_mode), (gst_text_overlay_setcaps),
(gst_text_overlay_text_pad_linked),
(gst_text_overlay_text_pad_unlinked),
(gst_text_overlay_set_property), (gst_text_overlay_getcaps),
(gst_text_overlay_shade_y), (gst_text_overlay_blit_yuv420),
(gst_text_overlay_resize_bitmap), (gst_text_overlay_render_text),
(gst_text_overlay_push_frame), (gst_text_overlay_pop_video),
(gst_text_overlay_pop_text), (gst_text_overlay_collected),
(gst_text_overlay_change_state), (plugin_init):
* ext/pango/gsttextoverlay.h:
* ext/pango/gsttimeoverlay.c: (gst_time_overlay_base_init),
(gst_time_overlay_render_time), (gst_time_overlay_get_text),
(gst_time_overlay_class_init), (gst_time_overlay_init):
* ext/pango/gsttimeoverlay.h:
Port pango-based textoverlay, timeoverlay and textrender to 0.9
and add background shading and text wrapping modes. Make
timoverlay derive from textoverlay. Also add new clockoverlay
element.