Adding storing of cookie when hitting enter or background (if checkbox
selected), was missing.
Updating widgets code to update only once even when plotting multiple
variables , moving around classes where they fit best.
Merge branch 'development' of https://github.com/openworm/org.geppetto.frontend.git into development
Adding requireJS library, implementing adding widget scripts through
requireJS (main.js file). Moving widgets folder inside js folder.