Remove unused variable

o heat/common/config.py:DEFAULT_PORT = 8000

  This variable was removed in the following commit.

    commit 34e47b64d926c055d9895c5b3f27949eaca68999
    Author: Steve Baker <sbaker@redhat.com>
    Date:   Mon Jul 22 16:01:44 2013 +1200

        Move heat-cfn, heat-boto, heat-watch to new repo

Change-Id: Iab6213eba1422882c92bd16a3351df19869aa9f3
Allow update of disable_rollback

Previously, any change to disable_rollback was ignored during
stack-update.

Change-Id: I76aaf5be379dab5347e392392b2334ab1d8749b0
Closes-Bug: #1290943
Replacing NetworkGateway when devices updated

Updating OS::Neutron::NetworkGateway failed when devices property changed.

Currently, NetworkGateway's devices property doesn't have update_allowed=True.
So, UpdateReplace have used when updating devices property.
However, Neutron doesn't allow that same Gateway Services ID exist at a time.
Eventually, 409 error occured by Neutron.

For avoiding above error, I implemented replacing NetworkGateway in handle_update.
The processing order is delete -> create. It can avoid the 409 error.

Change-Id: I4021610355d03eb6ca07272cb1e44ff2b31dfff9
Closes-bug: #1291901
Propagate files in nested stacks

Share files from the parent template in StackResource, to be able to
reference files in resources like AutoScalingGroup

Closes-Bug: #1294033
Change-Id: Id325690e4b1c42ef2b6463769da0ae99571e7a56
Order imports in alphabetical order (7/9)

This patch is one in a series to re-enable H306 style check rule
(imports are in alphabetical order). It touches roughly half of tests
(up to and including test_m*).

Implements: blueprint reduce-flake8-ignored-rules (partial)
Change-Id: Id1e10f7a519ceeb4339488760b36950440461edb
Merge "Replacing NetworkGateway when devices updated"
Merge "Allow update of disable_rollback"
Merge "Propagate files in nested stacks"
Merge "Order imports in alphabetical order (7/9)"
Merge "Remove unused variable"