Frontend: Fix system locale detection.

The locale detection would crash if no OCR tools are available, or if
system locale cannot be determined (i.e. LANG env var is not set)
Merge pull request #320 from plietar/fix-locale-detection

Frontend: Fix system locale detection.
README: add link to paperwork 0.1.3 archive

Signed-off-by: Jerome Flesch <jflesch@wyplay.com>
Frontend: Page editing: Make sure that thumbnails are correctly updated

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Backend: make sure that ~/.config exists

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Frontend: Make sure SIGINT and SIGTERM are nicely handled

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Frontend: Make sure Gtk.main_quit() is called if there is an exception raised during init

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Revert "Frontend: Make sure Gtk.main_quit() is called if there is an exception raised during init"

This reverts commit f1bc73dce7850a3eadb5a0f2a7f1150051043240.

That was stupid.
Frontend: About Dialog: Load the paperwork logo correctly

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Main window: Make sure the main window icon is correctly loaded

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Remove the shebang line in paperwork.desktop

Other applications do not have it. Moreover it makes debian’s lintian
trigger a warning.