Use the right node to extract the keystone settings

The keystone_helper needs to be called with the current node to extract the
correct keystone settings. Using the node with the keystone-server role is
wrong and breaks when keystone and cinder are deployed on different nodes.
Merge pull request #189 from rhafer/keystone-settings

Use the right node to extract the keystone settings
Add optional crowbar-applied boolean attribute to schema

Set it to false by default in the json and update proposal schema
version to 3.
Merge pull request #190 from bkutil/add_applied_attribute

Add applied attribute
Use a secure password for Cinder service

We really want to protect this from accidental
guessing.
Merge pull request #191 from dirkmueller/security

Use a secure password for Cinder service