share neutron admin auth tokens

Admin tokens in nova.network.neutronv2 were being created once per
"thread" (i.e., green thread) and shared. For example, during instance
creation, a single token was created then reused 6 times.  However,
this scheme was far from optimal. Given that tokens, by default, have
a shelf life of 24H, a single token can be shared by _all_ admin
nova.network.neutronv2 calls in a 24-hour period.

DocImpact
Signed-Off-By: Peter Feiner <peter@gridcentric.ca>
Closes-Bug: 1255594

Change-Id: I5c743aa86030e4ab000dcdefb6a7183305512303
(cherry picked from commit 5c01b9e618af44640332871757ff613b2f0b66e2)
Nova api service doesn't handle SIGHUP properly

When SIGHUP signal is sent to nova-api service, it doesn't complete
processing of all pending requests before terminating all the
processes.

Closes-Bug: #1334647

Change-Id: I3f7bd0ba5ef1bb716a97635252abe251053a669d
(cherry picked from commit 224a3de466d48301ab638b60ca47d19ad6b1b1dc)
Merge "share neutron admin auth tokens" into stable/icehouse
Merge "Nova api service doesn't handle SIGHUP properly" into stable/icehouse
Merge remote-tracking branch 'upstream/stable/icehouse' into stable/icehouse