Merge branch 'release-0.78.0' into develop

* release-0.78.0:
  Bumping version to 0.78.0
  Update opworks and sqs models
Dont fail tests if config file has sigv4 enabled

The unit tests should not be dependent on the values in your
config file.  This fixes a test failure where a test would fail
if sigv4 was enabled in the ~/.aws/config file.
Update S3 model to latest version

Fixes #392.
Merge branch 'fix-sigv4-unittests' into develop

* fix-sigv4-unittests:
  Dont fail tests if config file has sigv4 enabled
Don't import botocore, use fixed version

We'll need to update our tooling to populate this value,
but I believe this is causing the builds on readthedocs
to fail.
Merge branch 'fix-expiration' into develop

* fix-expiration:
  Update S3 model to latest version
Merge branch 'fix-doc-build' into develop

* fix-doc-build:
  Don't import botocore, use fixed version
Fix s3 integration tests on windows

Need to close the file before exiting the with statement,
otherwise we still have a reference to the file obj, which
means we can't delete the file on windows.
Fix pep8 formatting
Merge branch 'integ-windows' into develop

* integ-windows:
  Fix pep8 formatting
  Fix s3 integration tests on windows
Fix doc build on readthedocs

This uses the same approach as boto, which is to remove
sphinx from the requirements.txt file and create a separate
requirements-docs.txt file that contains sphinx for anyone wanting
to build the docs locally.
Enable use of page_size for clients
Merge branch 'fix-docs-2' into develop

* fix-docs-2:
  Fix doc build on readthedocs
Add a todo commnet for the test
Merge pull request #408 from kyleknap/client-page-size

Enable use of page_size for clients
Vendor six at version 1.8.0
Update the requirements and setup.py
Change rewording of import six
Merge pull request #411 from kyleknap/vendor-six

Vendor six to 1.8.0
Update elastictranscoder to latest version