Theme changes for OpenSeadragon replacement for ZoomIt

Dramatically simplifies the javascript in main.js.
Add OpenSeadragon plugin v0.3.1
Don't add non open source assets to the repo
Theme changes for OpenSeadragon replacement for ZoomIt

Dramatically simplifies the javascript in main.js.
Add OpenSeadragon plugin v0.3.1
Don't add non open source assets to the repo
Merge remote-tracking branch 'origin/openseadragon-redux' into openseadragon-redux