Correct protocol/action initial values provided to UpdateRule

Currently protocol/action initial values in UpdateRule are incorrectly
formatted: neutron returns lowercase protocol/action strings but
UpdateRule form expects uppercase strings as initial values which
implies to reorder protocol/action choices to select the right initial
values.

This change corrects initial values provided to UpdateRule which allows
to remove the trick in UpdateRule.__init__ and initial protocol/action
values become translatable.

Change-Id: I7145dd591581a7e5e3fb0591518d0e1564f38c10
Merge "Correct protocol/action initial values provided to UpdateRule"