trying to add develop for travis
Merge pull request #233 from ros/travis_fixes

trying to add develop for travis
Source installer cache should also return a list.

Updated the caching test and added the .rdmanifest dependency
checking test (which is failing at this point).
source installer: obey depends in .rdmanifest
Merge pull request #231 from jksrecko/master

Make rosdep obey dependencies in .rdmanifest

Thanks for the updates and tests!

Fixes #230
pep8 compliance updates
pep8 cleanup
pep8
pep8 and pyflake
pep8 and pyflake
pep8 and pyflake
Merge branch 'pep8' of github.com:ros/rosdep into pep8