Edits on help strings

Improve help strings for consistency. Fix wording, typos,
capitalization and add "." as appropriate.

Change-Id: I376f6d0269aee8dd0e67ffab6386eac2139844ab
Don't log sensitive auth data

This code change redacts the password in keystone request, and
also redact the token text in keystone response. The code still
makes REST call by itelf, instead of calling keystone client.

Closes-Bug: 1327019

Change-Id: Ib9c0610c1ef351a127364478721cf961c2a30125
Merge "Edits on help strings"
Merge "Don't log sensitive auth data"