run_tests.sh OS X script fixes

On OS X, '*' is not a valid grep modified for '[^[:space:]:]', nor is it
necessary when the lines being checked against must be prefixed with
neutron.tests.
Also, dirname was being called with an empty var, without quoting, resulting
in usage errors.

Closes-Bug: 1391858

Change-Id: I34ab0625a00809f68b7a44cb3a175a57ba0bd6d5
Strip square brackets from IPv6 addresses

When releasing old DHCP leases, square brackets around IPv6 addresses
should be stripped while reading dnsmasq hosts file.

Change-Id: Ia1e6d3a3cba30c94a1faa157d1d83da7beb523c4
Closes-bug: #1398380
Switch to using subunit-trace from tempest-lib

This commit removes the local copy of subunit-trace and instead uses
the version packaged with tempest-lib.

Change-Id: Ia7b57c6fc092514d9fbe4e71f580a4b189dc68b0
Remove broad exception catch from periodic_sync_routers_task

Although this change removes a broad exception from
periodic_sync_routers_task (neutron.agent.l3_agent), the
implementation still ensures if an exception --caught or uncaught --
prevents a call to the method to disable the fullsync, then the next
call to the method will perform a fullsync again.

Author:         Cedric Brandily <zzelle@gmail.com>
Co-Authored-By: Carl Baldwin <carl.baldwin@hp.com>

Change-Id: I6281886f3334100a18952578250c8154a0ed15a9
Migrate to oslo.context

That's just a matter of adding requirements.txt entry, fixing imports,
and dropping the corresponding oslo-incubator module from the tree.

While at it, made all imports to import the module into 'oslo_context' and
not just 'context', so that we don't override the module locally in
multiple methods that receive their context arguments with the same
name, making the library inaccessible from inside those methods.

Change-Id: Ie62af970b3b7f225de453e56c01abc4b12af8f5e
Closes-Bug: #1401054
Don't restore stopped mock that is initialized in setUp()

Since this mock will be reinitialized for consequent test cases when
calling setUp(), it's not needed to restart it in the case.

Change-Id: Ib120bf09d24dccc0b09fae906dae05c69efe734a
Merge "Don't restore stopped mock that is initialized in setUp()"
Merge "run_tests.sh OS X script fixes"
Merge "Switch to using subunit-trace from tempest-lib"
Merge "Strip square brackets from IPv6 addresses"
Merge "Remove broad exception catch from periodic_sync_routers_task"
Merge "Migrate to oslo.context"