add non-routed subnet metadata support

implements blueprint metadata-non-routed

This patchset completes Quantum metadata support by adding metadata
proxy support for isolated network segments.  The support requires that
the guest instance request host routes, so that the DHCP port can be
used to proxy metadata requests. NOTE: The cirros image does not support
host router, so the UEC or equivalent required for testing and usage.

Change-Id: I962deef7c164ecb2a93b7af326ef8dca6e2b183a
Merge "add non-routed subnet metadata support"
Imported Translations from Transifex

Change-Id: Iba8087a9aba3b75907f19c8ffbf2939a90ea0e61
Improvements to API validation logic.

Do not automatically map generic exceptions like AttributeError to
http errors (instead they should be handled closer to where they occur
so that they can be "intelligently" converted to the appropriate
error).

Fix up some expected error codes in the unit tests.
Improve some of the validation messages.
Remove all use of locals() in attributes.py

Fixes: bug #1076813
Change-Id: Iabf8808a840e927307bbcae4cd41790af3d79a9e
Sync latest cfg from oslo-incubator

Main cfg change is:

  e3e5e0e Fixes "is not", "not in" syntax usage
  d156150 Implements import_group

Change-Id: Ie6c0fe0d9d35ef6178a121e4f566207576c8d1e6
Implements quantum security groups support on OVS plugin

implements bp quantum-security-groups-iptables-ovs
- Adding [SECURITYGROUP] firewall_driver to the conf
- Adding NoopFirewallDriver
- Adding OVSHybridIptablesFirewallDriver
- Refactoring security group code to support OVS plugin

Change-Id: I7aabc296265afc47d938121543ace57cce6cc521
Merge "Improvements to API validation logic."
Imported Translations from Transifex

Change-Id: I3a619c2e95c417169a281986e3d28044383075ca
fix grammar in NetworkInUse exception

bug 1121555

Change-Id: Ie06ef45d066505b0ec1cd31e73c43ae6985afcde
Merge "Sync latest cfg from oslo-incubator"
Merge "Imported Translations from Transifex"