Flush the clipboard before closing it, not after
Disable a bunch of ICU stuff we don't use

Bumps ~800KB off the executable (and 100MB off icu.lib).
Add a bunch of missing project references
Pull even more of the subs load logic into Project

The relative order of the on-file-load logic matters, so signals don't
work very well for it. Doing it all explicitly in Project fixes a bunch
of inconsistent issues related to restoring saved state.

Closes #1759.
Use the customized default styles for SRT files opened from matroska