Create add embedded video option in twitter clone

Deliverables are: 1.) Create and add a new video upload button next to current upload image button; 2.) Make the new video button work and use the same interface as the upload images option does, to upload embedded videos; 3.) Make it possible that by using the new video upload button videos can be uploaded from: youtube, metacafe, 123video 4.) Make sure the video is displayed and added exactly the same way as images are added as a tweet; 5.) Using the same style and layout as the current image option. Build in a pre content check that only embedded videos can be added using this option not images.