Make news banner optional via config
Initial Webm Support
New dependency
Add very hacky support for pdf uploads

I wouldn't actually recommend using this. At all.
Merge branch 'master' into m
Merge branch 'OptionalBanner' into m
Merge branch 'HackyPdfSupport' into m

Conflicts:
	Gemfile
	app/models/post/file_methods.rb
Update gems.
Only catchall GET and POST requests.
Update gems.
Add webm preview for url upload
Merge branch 'WebmSupport' into m
Merge branch 'upstream'