Add support for https requests on nova metadata

Adds new config value for accessing nova metadata api with SSL. In case
nova api requires client certificate other config values were added
providing client certificate and client private key.

DocImpact

Closes-bug: #1293587
Change-Id: I782a12eb77553f4369b782071b4ad19efb82e5e2
ofa_neutron_agent: Fix _phys_br_block_untranslated_traffic

Install the flow to the correct bridge.

Closes-Bug: 1301142
Change-Id: I2aa7ffd6bb297837a39cdd00794af100bf9ab407
Merge "ofa_neutron_agent: Fix _phys_br_block_untranslated_traffic"
Merge "Add support for https requests on nova metadata"