Allow for relative paths by using abspath

relative pathing comes in handy on occasion, particularly when
delegating to localhost and running some command out of your playbook
repo. Making use of os.path.abspath will allow for the full path to
chdir and executable to be discovered if not provided.
increase test coverage of inventory by around 5% according to nose
Fixing typo in EC2 modules
Minor cleanup of CHANGELOG for 1.3
Merge pull request #3915 from jlund/changelog-cleanup

Minor cleanup of CHANGELOG for 1.3
Update changelog
Update releases
Fix for "argument must be an int, or have a fileno() method" error

The issue was that, when forks == 1, the _executor() function was
being called with None for the value of new_stdin.

Fixes #3841, #3902
Support multiple --extra-vars flags
Merge pull request #3913 from jlund/ec2-typos

Fixing typo in EC2 modules
Merge branch 'add_tests' of https://github.com/mscherer/ansible into mscherer-add_tests
Merge branch 'command-relpath' of https://github.com/j2sol/ansible into j2sol-command-relpath