[gthumb] (15 commits) ...added burn_disc to default extensions

[Paolo Bacchilega <paobac src gnome org>]

Summary of changes:

  fbf745c... no need to call gdk_thread_init
  af19236... added check for the libbrasero library
  b378954... added the burn_disc extension
  a756586... always try to load the requested file
  51e11ca... check whether the comment file is not null before using it
  e3497cd... [burn_disc] add the sidecars in the relative subfolders
  295b256... [burn_disc] added ability to specify the disc name
  e909bad... updated the POTFILES
  b3ceaf4... [burn_disc] do not expand the options
  9c490c0... allow the user to write to disc the current folder recursiv
  2d55dcd... [burn_disc] do not create empty folders
  85c2f64... [burn_disc] converted the burn procedure to a task
  f9700f6... Merge branch 'export-to-disc'
  1eceb29... updated POTFILES.in
  4b94196... added burn_disc to default extensions