Merge pull request #16 from voldyman/ui-tweaks

Ui tweaks
transitioned the about dialog to use Gtk.AboutDialog
Merge pull request #18 from voldyman/gtk-about-dialog

transitioned the about dialog to use Gtk.AboutDialog
Fixed a bug related to the menu button invisible on certain DEs

I mixed up label_widget and icon_widget, which caused strange behaviour.
The label_widget is now a proper text label saying "Menu", whereas the
icon_widget is the actual icon.
Use less λs so as to make debugging easier.

fixes #20
one function to handle two events
removed temporary file (added accidentally)
Merge pull request #21 from voldyman/less-λ

Use less λs so as to make debugging easier.
Update README.md
Updated the link to the windows build
MainWindow redesign, removed toolbar