Uploaded video not readable in some browsers

[woecifaun]

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Uploaded video from Apple devices are not readable on Google Chrome and buggy on Apple Safari. Not tested on Internet Explorer or Opera.

Hint: The mimetype of an uploaded video had to be forced to video/mp4 when extension is .qt.
See here: https://github.com/afup/haphpy-birthday/blob/master/src/AFUP/HaphpyBirthdayBundle/HttpFoundation/File/File.php#L19