Add string 'quantum'/ version to scope/tag in NVP

This patch adds scope='quantum', tag=QUANTUM_VERSION to each element
created in NVP via quantum. This patch also removes the function
set_tenant_id_tag() as it was only used in one place and wasn't very useful.

Fixes bug 1128674

Change-Id: I9f1f8e9b49154012a82d24e31cc9fb7f2df9c604
Make the 'admin' role configurable

Bug 1158434

This patch adds a new policy named 'context_is_admin' which defines
an admin user as a collection of roles or else. The quantum context
has been updated to check for this policy when setting the is_admin
flag.
This patch also adds a method for gathering 'admin' roles from policy
rules as current logic requires the context to be always populate with
the correct roles for admin rules, even when the context is implicitly
generated with get_admin_context or context.elevated.
Backward compatibility is ensuring by preserving the old behavior if
the 'context_is_admin' policy is not found in policy.json

Change-Id: I9acea75cca0c47e083a9149e358328ea3ca12d68
Metadata agent: reuse authentication info across eventlet threads

Fixes bug 1152429

Change-Id: Ib65f08a46feb14abc97c0c83e57d076abd372a2c
lbaas: check object state before update for pools, members, health monitors

Fixes bug 1166365

Change-Id: I027bb1465ab08a643a02bddea30db82652be55ed
Merge "Add string 'quantum'/ version to scope/tag in NVP"
Merge "Metadata agent: reuse authentication info across eventlet threads"
Merge "lbaas: check object state before update for pools, members, health monitors"
Imported Translations from Transifex

Change-Id: I80e45f91d74c197d81a561379c0740a6d9aa4d68
Merge "Make the 'admin' role configurable"
Merge "Imported Translations from Transifex"