Added KeyModifiers
Text selection
Added Panel.MousePos
Added Label.GetLetterAt( pos )
Send an onmousemove to active element
Added Label.ShouldDrawSelection
Added TextEntry mouse drag selection
Lable: don't be 0,0 if string is empty, be the normal line height
Only count as a double click if the cursor didn't move significantly
Added Panel.OnDoubleClick
Select word if double click
Merge branch 'master' of sbox