Adding front-end functionality for multiple new window open of LTI.
Updating from with new signature.
Add tests and fix.
Fixing failing python test.
Add getting client and  secret tests.
Modernized LTI JavaScript code.

A proper constructor. All functions are now in the LTI object's prototype.
The idea is to make it easily testable.
Adding comments to JS code for LTI.
Adding further comments to LTI JavaScript module.
Add signing body tests.
Refactor.
Simplify test.
Add tests.
Adding Jasmine tests.
Fixing Python LTI tests.