Update installation.rst

Fix a few typos and make a clear distinction between installation and configuration steps.
Upgrade to be compatible with Django 1.5
2.0b11
Fixed a bug that happens when subscription is None
Merge pull request #31 from epicserve/master

Fixed a bug that happens when subscription is None
2.0b12
Start a test suite
Remove lame print statement
Add note about running test suite
Add a test runner
Add some more tests to validate customer linking
Fix single-quotes
Add travis integration
Fix readme formatting
Fix readme formatting
Fix Travis CI image
Fix travis config
PEP8 Fixes
Drop support for 2.6
Drop Python 3 targets for now

There seems to be something about the packaging/setup
that breaks in Python 3 environments.