Feature/youtube upload

as we need ffmpeg for video to mp3 conversion you need to run vagrant provision
i needed to increase the memory of our vagrant vm for the ffmpeg conversion

* added backend resource to upload videos to the server via youtube link to the video

* added backend resource to search for videos on youtube

* added frontend page for youtube upload
![youtube_upload](https://cloud.githubusercontent.com/assets/1226573/5564184/b210af7e-8eae-11e4-85c8-e108af0f54b9.png)

@rieder91 is this change okay for our build system?
if so ... i´m fine with it, just thought that changing the vagrant without special need might not be that good