(Hopefully) improve a few Dutch translations, add missing ones up until cyberdisc autopsy
Add several more ufopaedia and mission briefing texts, including game over/endgame stories!

Changed a few texts for consistency to the informal "je" form.  In some sentences formal and informal were even mixed!

Use UTF-8 rather than Latin-1.
More translations, up until STR_ACCESS_LIFT_UFOPEDIA
More Dutch translations, up until STR_ALIEN_BASE_UFOPEDIA
Finish Dutch translation
Fix string keys to match all English versions
Shorten some strings that ran out of space
Dutch translation tweaks

- Try to more consistently maintain passive voice for action buttons.
- Shorten some more texts which ran off the screen.
Dutch translation: use more natural "conjugation" for etherials, and a less silly name for reapers.  Shorten ufopaedia-text for mutons
Dutch translation: Some more ufopaedia-text fixes
Merge pull request #629 from sjamaan/master

Dutch translation