app: +peripherals, hooks: resturctured, screens:ud

app:    added a peripheral folder to host common config files that are used
by qtile_config.app. i.e. Conky as wallpaper
        Put all the hooks.startup apps into app (i.e. wpa_gui -> app.netGui)

hooks:  adapted to use app.APP instead of hardcoded programs.

screens: undone notify widget - raises strange errors and does not work
anyway. Will have to look into that (TODO)