How to align a RibbonPageGroup to the right side of a page?

This example demonstrates how to create a custom RibbonControl that displays a group with the "AlignRight" tag assigned at the right side.

Updated:

The example was slightly modified to dispose of a gap which occurs after merging (see  Support correct RibbonPageGroups alignment with no gap on ribbon merging).
To enable correct operation, a RibbonPanelComplexLayoutCalculator descendant was created, and the UpdatePanelLayout method was overridden in it.