Remove version from keystone identity_uri

Otherwise the services can not autoselect the right keystone
version for authenticating tokens.
Merge pull request #222 from dirkmueller/fix_admin_auth

Remove version from keystone identity_uri
add the user/pass to the keystone_settings hash

The intention is to move the code duplicated in each
cookbook (e.g. cinder, ceilometer, nova) from COOKBOOKHelper into this
central KeystoneHelper where it can be used by all of them.
refactor chef search and result processing