Equipment/Inventory dialog now shows item stats using the classic tooltip

Made tooltips much faster, moving the mouse over the hotkeys list should not lag anymore
Tooltips now internaly use tstrings, you can pass a tstring to Tooltip:set()


git-svn-id: http://svn.net-core.org/repos/t-engine4@2267 51575b47-30f0-44d4-a5cc-537603b46e54