widgets: refactor data structures

Ref e7bbeb42dce8f69f3f18540d09b2a50e5256dc1b
widgets/desktop: split window_title to own widget

All globals have also been removed from these widgets.

Conflicts:
	src/widgets/desktops.c
	src/widgets/widgets.h
widgets: handle widget disable flags from autotools
widgets/battery: get rid of globals
widgets/weather: fix segfault on HTTP request and JSON decode error
Merge branch 'feature/refactor-widgets' into develop