Port dvdsubdec to 0.10

Port dvdsubdec to 0.10

Original commit message from CVS:
* configure.ac:
* gst/dvdsub/Makefile.am:
* gst/dvdsub/gstdvdsubdec.c: (gst_dvd_sub_dec_base_init),
(gst_dvd_sub_dec_class_init), (gst_dvd_sub_dec_init),
(gst_dvd_sub_dec_finalize), (gst_dvd_sub_dec_src_event),
(gst_dvd_sub_dec_get_event_delay), (gst_dvd_sub_dec_parse_subpic),
(gst_get_nibble), (gst_setup_palette), (gst_get_rle_code),
(gst_draw_rle_line), (gst_dvd_sub_dec_merge_title),
(gst_send_empty_fill), (gst_send_subtitle_frame),
(gst_dvd_sub_dec_advance_time), (gst_dvd_sub_dec_chain),
(gst_dvd_sub_dec_sink_event), (gst_dvd_sub_dec_handle_dvd_event),
(plugin_init):
* gst/dvdsub/gstdvdsubdec.h:
Port dvdsubdec to 0.10