Make font encoding UTF-32LE, add full Cyrillic + Latin Extended A

This commit changes the font encoding (kanji_encoding) to UTF32-LE to
allow using the full Unicode for fonts. Also, it adds the Cyrillic Unicode
block (except pre-1917 letters) and a complete Latin Extended A Unicode
block.

This adds support for Polish, Czech and many languages with no known
published games (Belarusian, Ukrainian, Serbian, Macedonian, Latvian,
Lithuanian, Turkish; also Tatar, Kazakh if encoding 65001 is used).

Unless explicitly stated otherwise (in the commit message), all the
changes I am commiting are available under the Creative Commons Zero
license.
Cleanup: kanji_encoding is no longer used
Merge pull request #245 from rohkea/master

Make font encoding UTF-32LE, add full Cyrillic + Latin Extended A