Merge pull request #120 from rossbruniges/dev

Adding in resource template for new learning web RTC data learning lab
Merge pull request #124 from rossbruniges/dev

fix #123 - fixing edit entry url
Fixed the "untitled" link_node in the walkthrough. Now it reads "Contributers".
Discovered and fixed a bug whereby the demo link would not disappear if a user seeked to a previous part of the video.
Added 4th Learning Lab interactive video.
Adding in a new template for thw WebSockets lab