Make Media Vimeo's WYSIWYG insert autosubmit code more specific, non-destructive

Problem/Motivation

Right now Media Vimeo sets the autosubmit setting for WYSIWYG inserts to true if the file is a video and false otherwise. Two problems:

1. It hijacks the autosubmit setting for all video files, preventing any custom settings for youtube/local videos/etc.
2. It overwrites any autosubmit value set before it, i.e. if you have a module that sets image file autosubmit to true and Media Vimeo's hooks are called afterward it will check if the file is a video and if not set autosubmit to false. Bummer.

Proposed resolution

Check to see if mimetype is media/vimeo, and if so set autosubmit to true. More specific and only fires on vimeo files.

Related Media Youtube issue at #1572798: Make Media Youtube's WYSIWYG insert autosubmit code more specific, non-destructive.

Patch to follow.