-Merge: documentation updates from 1.4 branch


git-svn-id: http://svn.openttd.org/trunk@27032 6aa0318a-3be1-0310-93fa-89fd2396df07
-Codechange: Generalize GetTextfile for multiple extensions
  - Instead of hardcoding the .txt extension in a printf string, it is
    now stored in an array of possible extensions. This array still only
    contains .txt, so behaviour is unchanged, but this makes it easier
    to add other extensions later.

git-svn-id: http://svn.openttd.org/trunk@27033 6aa0318a-3be1-0310-93fa-89fd2396df07
-Feature: Support .txt.gz changelog, readme and license files in basesets, newgrfs, etc

git-svn-id: http://svn.openttd.org/trunk@27034 6aa0318a-3be1-0310-93fa-89fd2396df07
-Feature: Support .txt.xz changelog, readme and license files in basesets, newgrfs, etc

git-svn-id: http://svn.openttd.org/trunk@27035 6aa0318a-3be1-0310-93fa-89fd2396df07
-Fix [FS#6148] (r26928): crash when changing smallmap colour when the smallmap window has not been opened yet


git-svn-id: http://svn.openttd.org/trunk@27036 6aa0318a-3be1-0310-93fa-89fd2396df07
-Fix [FS#6150] (r26878): m6 was moved from Tile To TileExtended, but it wasn't properly removed from Tile (patch by Juanjo)


git-svn-id: http://svn.openttd.org/trunk@27037 6aa0318a-3be1-0310-93fa-89fd2396df07
-Update from WebTranslator v3.0:
belarusian - 21 changes by KorneySan
catalan - 2 changes by juanjo
czech - 14 changes by Eskymak
russian - 1 changes by KorneySan


git-svn-id: http://svn.openttd.org/trunk@27038 6aa0318a-3be1-0310-93fa-89fd2396df07