WINTERMUTE: Save frames as uint rather than long

It's just as good: at 30 FPS, this allows for
2 ^ 32 / 30 / 60 = 2386093 mins, which is, I guess, a reasonable limit.
WINTERMUTE: Preserve const when handing chars over to drawText
WINTERMUTE: Add clarification comment in loadSubtitles
WINTERMUTE: Turn display() and update() into void functions.

No idea why they were bools in the first place.
WINTERMUTE: s/uint32 _lastSample/long _lastSample/
WINTERMUTE: Turn a bunch of uint into uint32 in VideoSubtitle
WINTERMUTE: Rename VideoSubtitle to SubtitleCard
WINTERMUTE: Use full braces for blocks in Videosubtitler
WINTERMUTE: Avoid doing check before delete (deleting 0-pointer is safe)
WINTERMUTE: Rename VideoTheoraPlayer->_subtitles to _foundSubtitles for clarity
WINTERMUTE: Lose unnecessary if() in VideoTheoraPlayer
WINTERMUTE: Introduce BaseGame->expandStringByStringTable(&Common::String)
WINTERMUTE: Don't bother inheriting BaseGame in SubtitleCard
WINTERMUTE: Remove useless constructor from SubtitleCard.
WINTERMUTE: Const'fy members of class SubtitleCard
WINTERMUTE: Use BaseGame->expandStringByStringTable(&Common::String) in SubtitleCard
WINTERMUTE: s/delete array/delete[] array/
WINTERMUTE: Use int32 for _lastSample in VideoSubtitler

We are thus making room for the sentinel == -1
WINTERMUTE: Initialize tokenSomething vars in VideoSubtitler

MSVC complains otherwise.
WINTERMUTE: Turn _subtitles into Common::Array<SubtitleCard> in VideoSubtitler

This necessarily loses const in SubtitleCard's attributes