2.14.5 stuff:

- Explicitely adjust the effective GID before running the child session
  program to avoid remaining with high privileges.  Fixes bug #340347.

- Updated config/gettextfoo.h to reflect current strings for translation.
  Fixes bug #340017.  (Brian Cameron)

- Updated comments in GDM configuration files (Brian Cameron)

- Translation updates (Takeshi AIHANA, Josep Puigdemont Casamaj\303\263,
   Artur Flinta, Priit Laes, Chao-Hsiung Liao, Lukas Novotny, Daniel
   Nylander, Ignacio Casal Quinteiro, Francisco Javier F. Serrador,
   Alexander Shopov, Funda Wang)