Change to only regenerate a thumbnail if one with the same name doesn't already exist in storage
Merge pull request #327 from frankier/fixup_cache_existing

Only regenerate a thumbnail if one with the same name doesn't already exist in storage
Fix Travis test running so broken tests are reported rather than just flake8
Enable travis-ci for all branches
Fix flake8 travis command
Fix tests
Add test to check that if thumbnails exist on disk but not in the KV-Store, they will be added back into the KV-Store
Merge pull request #331 from frankier/test_clear_doesnt_regenerate

Add test to check that if thumbnails exist on disk but not in the KV-Store, they will be added back into the KV-Store
Merge pull request #330 from frankier/fix_tests

Fix tests
Merge pull request #329 from frankier/fix_travis

Fix travis building of tests
Set failfast default to false
Update current.py

JPG causes a KeyError: u'JPG' in 

sorl/thumbnail/base.py", line 196, in _get_thumbnail_filename
  EXTENSIONS[options['format']])

because there is JPEG used instead of JPG:

base.py:
EXTENSIONS = {
    'JPEG': 'jpg',
    'PNG': 'png',
}
Merge pull request #332 from g10f/patch-1

KeyError: u'JPG'
Add two new variations of clear to delete thumbnail files