settings module

[superdachs]

set global things like:

• behavior of editor (tab to space, numbers, font, theme, linewidth, autoindent etc)
• username/email

[superdachs]

715c31c
file handling for corrupt configfile and changes in configuration not working yet.
settings window has no content and listeners implemented yet.

[superdachs]

config has to be refactored. (branch: feature/settings_refactoring)