Extend photos tests to test usage of newly added filename timestamp.
Add tests for movies.
Fix issue with the representation of miliseconds
Remove unneeded import
Improve support for configurations with or without file prefix.
Replace dependency on PIL with Pillow.

Description:
The package PIL appears to be unmaintained since 2009. The fork Pillow is
compatible and alive.
Update dependencies in README.
Add Olympus RAW format (orf) to the list of recognized extensions.
Replace tabs with spaces.
Add handling of exceptions that appeared in real use.
Fix exception handling to support different Python versions.
Merge pull request #6 from silvavlis/master

Update tests and change dependencies