Fixes TypeError on Client instantiation

When instantiating novaclient with kwargs or named attributes, the 'password'
field is duplicated due to an overwrite on the __init__ method of Client v2.
This patch pops out the password field when it's passed and no api_key is
provided.

Co-Authored-By: Pavel Kholkin <pkholkin@mirantis.com>

Closes-bug: #1511417

Change-Id: Id8310eccef5f0f9a2983e25dd35541d1eb0efe86
2 files changed