Added BEI backend functionality (actual data return still stub, but is dynamic).
Tab CSS Style update
Video resource now returns a video thumbnail in base64 format
BEI backend up and running.
New abstract class method added in BaseResource

`is_valid_observation(observation)` should return true if the observation is compatible.
VideoResource updated to demonstrate implementation
Merge pull request #65 from blackhydrogen/basic-encounter-info

Basic encounter info
Minor Bug Fix
Main template now sets the encounter ID and static path in the sewi variable
Main script now passes the encounter ID to configurator
Merge pull request #66 from blackhydrogen/resource-video

Video resource now returns a video thumbnail in base64 format
Merge pull request #67 from blackhydrogen/resource-audio

Added Tool Tips
Merge pull request #68 from blackhydrogen/configurator

Bug fixes and visual updates for tab container
Merge pull request #69 from blackhydrogen/boilerplate

Backend logic updated, encounter actual URL now functions