Initial glade version

[Nacho <nacho resa gmail com>]

Hi,
I've committed a lot of changes.
Now gtranslator works with libglade.
There are a lot of bugs like:
 - History, dnd, bookmark is not working.
 - When you open a po file, first message not appear.
 - Status radio buttons are not working well.
 - Plural tabs should not appear if there aren't plural forms in the message.
 - Progress bar is not working becouse current_page->po->translated variable returns always 0.

Something else?

Regards.