Submerge 3.2

- Subtitle rendering re-written from scratch. Uses less memory.
- Support for WebVTT cue settings, ie positioning and such.
- Using WebVTT you can place subtitles anywhere within the video frame.
- Subtitles are updated in real-time when you edit the subtitle file in a text editor.
- The export menu is now disabled until embedded subtitle tracks are fully parsed.
- Fixed a bug where a malformed font tag would make Submerge eat a huge amount of memory.
- New 4k UHD (2160p) export preset. It's not fast, but it works!
- FFmpeg updated to the 2.6.2 "Grothendieck" release.
- Various bug fixes and improvements for lower-end Macs.