Video Upload Errors

[fitzgerald]

Not sure when this broke, but video upload is erroring,

To repro:

1. Assets tab
2. Upload Asset
3. Select an mp4 under 5MB

500 occurs.

[danigirl329]

In app/models/asset.rb there was a new constant introduced called APPROVED_CONTENT_TYPES and that is being used to process uploads but it should be using clippedextension AssetTypes so that one can override in the config files of the parent application.