libhb: remove emptry tx3g subtitles

We don't need the empty subtitle buffers.


git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@6373 b64f7644-9d1e-0410-96f1-a4d463321fa5
libhb: fix merging of ssa subtitles

mergeSubtitle was originally written for pure text subs.  But now the
subtitle buffers have extra ssa formatting that needs different treatment.


git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@6374 b64f7644-9d1e-0410-96f1-a4d463321fa5
libhb: fix tx3g styles when the entire line is one style

the style was not getting flushed if there were no style changes


git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@6375 b64f7644-9d1e-0410-96f1-a4d463321fa5
libhb: fix small error in "empty" mp4 subtitle duration


git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@6376 b64f7644-9d1e-0410-96f1-a4d463321fa5
MacGui: removed unused outlets in PicturePreview.xib.

git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@6377 b64f7644-9d1e-0410-96f1-a4d463321fa5
MacGui: realigned the video quality options.

git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@6378 b64f7644-9d1e-0410-96f1-a4d463321fa5
WinGui: Update the Gong WPF Drag/Drop library. This fixes a few issues with the moving/ordering of Audio/Subtitle and Queue items.

git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@6379 b64f7644-9d1e-0410-96f1-a4d463321fa5