Add spoken language selector to the new task flow

[Amdrel]

Description

Resolves #191

This patch adds an optional language dropdown that lets users specify which language is being spoken in a video. This dropdown's options map to every known existing video language category currently in Commons. Examples of language categories include but are not limited to, "Videos in English", "Videos in Korean", "Videos in German", "Videos in Farsi", etc.

The ticket makes reference to having music be in there too, but I left that out for now. There might be better ways to infer that such as with file metadata. It's also not a language and looks misplaced in the dropdown.

Changes

• Add new optional "Language" dropdown to the target page in the new task dialog.
  • This dropdown only renders if both audio and video are being imported.

Screenshots

[Amdrel]

Ah dang it. It looks like the action doesn't automatically push commits for forks due to permissions issues... I'll push the minified files here shortly and it should be able to verify them. This problem can be solved by keeping minified files out of the project and generating them as part of a deploy step (the proper way).