softsubtitles:

softsubtitles:
- when doing an indepth scan, do not scan CC tracks
- separate subtitle configureation attributes into separate
  hb_subtitle_config_t.  Add an instance of this to hb_job_t for
  setting the attributes of the subtitle found through an indepth scan
- Add a default_track flag to hb_subtitle_config_t that tells the muxer
  that the track should be flaged as the default. muxmkv uses this.
- When an indepth scan is complete, check to see if the autoselected
  subtitle matchces (by id) one of the manually selected subtitles.
  If a match is found, the autoselected subtitle with all the attributes
  the user assigned to it replaces the manually selected subtitle.
- LinGui: Add "Default" column to subtitle tab.  This is a radio that lets
  the user choose which subtitle should be displayed by default.

git-svn-id: svn://localhost/HandBrake/trunk@2468 b64f7644-9d1e-0410-96f1-a4d463321fa5