Remove modified from FileMetadata.

Was was never used and never tested.
Merge branch 'nodate' into develop
Reduce length of log lines.

Only write the class simple name and whole seconds.
Merge branch 'simplename' into develop
Add find duplicates feature.
Merge branch 'finddupes' into develop
Refactor to make a real FileSet.

Previously, a "FileSet" was a Map. I changed it so that it is a real
class that abstracts the Map. I moved the static methods of
FileSetOperations to this class.
Split FileStore into multiple interfaces.

I split FileStore into FileStore, FileStoreSink, and FileStoreSource. I
did this primarily because FileStoreFlickr can't act as a source so it
was awkward to throw from one of the methods.
Merge branch 'refactor' into develop
Refactor to reduce method size.

Made methods in FileStoreFlickr shorter.
Added a constructor to FileMetadata to allow creation with params.
Add a convenience method for when regex not required.
Merge branch 'refactor' into develop
Merge branch 'develop'