v0.14.0: Merge pull request #360 from dustin10/filename-property-guessing

Add a convention-based way to guess the filename property to use for a given mapping

v0.13.0

Update UPGRADE guide for v0.12.0 to v0.13.0

v0.11.3: Merge pull request #348 from zeliard91/master

Fix Gaufrette storage : metadata key with path + force overwrite