Custom popup for textccolumns can now be added

#3522
fix cs errors

A24group/Triage#3522
Merge remote-tracking branch 'origin/hover-popup' into alecTextColumnCellChanges
Added functionality to optionaly show the popup

Added functionality to optionaly show the popup. Override the
"showPopup" function when creating an instance of the ssTextColumn.

If true is returned by "showPopup" then the popup will be displayed

issue A24Group/Triage#3522
Merge pull request #200 from A24Group/feature-custom-tooltip-textcolumn-3522

Custom popup for text columns
Merge remote-tracking branch 'upstream/master' into textColumnSpacer

Conflicts:
	src/org/ssgwt/client/ui/datagrid/column/SSTextCell.java