Reordering of optional and required args in lbaas commands help

In help info required args are changed to go after optional. The change
affects 'lb-healthmonitor-create' and 'lb-member-create' commands.

Fixes bug 1157502

Change-Id: I5bb2337796c8b725333ed23a662061a4f276985c
Merge "Reordering of optional and required args in lbaas commands help"