[FIX] sap.m.IconTabBar: Overflow list is now aligned at bottom right
[FIX] sap.m.IconTabBar: Overflow list is now aligned at bottom right

This change reposition the overflow list at the bottom right
corner of the button. This is requirement by visual spec.

BCP: n/a

Change-Id: I3c0ddfc23b417c2005711fa6fc6f796d590ab0dd

SAP/openui5,cschuff/openui5,cschuff/openui5,SAP/openui5,SAP/openui5,SAP/openui5,cschuff/openui5