Add Travis CI config file matching tox.ini file

Fixes gh-30.
Merge pull request #32 from treyhunner/travis-ci

Add Travis CI config file
Add ModelTracker test for save(update_fields=[...])
Fix ModelTracker for obj.save(update_fields=[...])
ModelTracker: check DB after using update_fields
ModelTracker: pass kwargs to parent save correctly

Fixes usage of update_fields in save()
Add test for ModelTracker before first model save
Update tox.ini for release of 1.5.
Bump version to 1.3.0.
Fix BooleanField default (for Django trunk)
Add badge for Travis CI to README file
Merge pull request #35 from carljm/travis-badge

Add badge for Travis CI to README file
Merge branch 'master' of github.com:carljm/django-model-utils

* 'master' of github.com:carljm/django-model-utils:
  Add badge for Travis CI to README file
  Fix BooleanField default (for Django trunk)
Bump version for dev.
Updated changelog.
Update LICENSE year to 2013