* app/app_procs.c: if we cannot load the font we'd like to use,
use the gtk+ default font. Fixes bug #8359.

* app/about_dialog.c
* app/install.c: properly ref/unref fonts

* app/text_tool.[ch]: code cleanup (do not rely on TRUE being 1)

* app/tips_dialog.c: code cleanup and less resizing


--Sven