Fixed drop and drag directive and some extras

* Corrected drop and drag directive
* Added comments
* Increased possessions max width when in compact mode
Made drop and drag tweaks

* Cards were blocking each other in relative pos. Changed to absolute
* Added z-index to cards and sidebar to prevent cards appearing on top
of sidebar
* Added explicit left border
* Card is now appended to end of content element's children on mouse up
so last clicked card is always above others.
Merge pull request #23 from goddamage/Issue-#2

Issue #2