widgets/desktops: update method of fetching desktop and window properties

Based on ewmhstatus, which basically also tells XCB to not trigger more property
change events for windows if the first request failed (e.g. if the window title
couldn't be retrieved).

https://github.com/baskerville/ewmhstatus
Removed statically assigned array.

Utilized snprintf and malloc to dynamically allocate script variable.
Removed statically assigned array.

Utilized snprintf and malloc to dynamically allocate script variable.
Merge branch 'develop' of github.com:nHurD/wkline into develop

Conflicts:
	src/wkline.c
Merge branch 'develop' of github.com:Lokaltog/wkline into develop
Merge branch 'develop' into plugins