Issue #2182093 by ThisIsDog, Gábor Hojtsy, alexpott: Remove outdated todo in Language class docs
Issue #2083733 by maartendeblock, JurgenR, Cyclodex, Pixelstyle, tankerjoe: Add reinstall instructions to INSTALL.txt
Issue #2182027 by InternetDevels, michaellenahan, tstoeckler: Fix docs for LanguageDefault class