[MARKET-161] - Changed category namespace from global to hierarchical
[MARKET-165] - moved overflow-y from html to body, changed html overflow to hidden and specified both heights to 100%
[MARKET-163] - added maximum height to modal and adjusted content to fit this change.
[MARKET-162] - moved close button up and added bigger top padding to modal
[MARKET-161] - Added unit tests
Merge pull request #43 from graimundo/5.2

Cherry picked features tested in master for 5.2