Add the Openstack SDK project to projects.txt

Change-Id: I629ae3296f683c0d26c2ae3a2b1a2fc1ef98d6da
Add retrying to global-requirements

Retrying is an Apache 2.0 licensed general-purpose retrying library,
written in Python, to simplify the task of adding retry behavior.

Retrying would be useful for the following projects:
- glance
- oslo
- nova
- certainly more...

Useful in the context of:
- session timeout
- retry on specific exception
- etc.

Change-Id: I11c20997d6b7ce37943b55c759845a3e655c84d3
Pin httpretty's precise version.

The latest release, 0.8.1, has completely broken installation, so for now block
it: https://github.com/gabrielfalcao/HTTPretty/pull/175 Can be unpinned once
they issue a release with a fix.

The 0.8.2 release is also broken, so exclude both of those releases.

Sounds like the fix is in 0.8.3 which is on pypi now.

Closes-Bug: #1332266
Change-Id: I42376a11cbba58184f3dd99245e0b39136d88ff4
Merge "Add the Openstack SDK project to projects.txt"
Bump up minimum cliff version to 1.6.0

OpenStackClient uses --max-width and the value formatter, both introduced
in 1.6.0.

Change-Id: I17a9fd335e2a3b746ddb069f13bf6cf710b38118
Merge "Add retrying to global-requirements"