Preserve EXIF tags when resizing
Read EXIF tags and put them in the media context
Make copying EXIF data optional
Add a test case for copying EXIF data
Make EXIF reading more robust and streamlined
Insert 'exif' and 'raw_exif' keys into media_ctx
Add datetime object to media.exif
Set the (overridable) locale

If the locale is not set, the user might be surprised to see strftime() output
to be in English rather than in his native language.
Merge pull request #25 from matze/exif-support

Add EXIF support