LTI module with tests
Remove ipdb.
Change h2 to h3
Fixing issues found by Anton during review of PR 804.

Changed use of IDs to classes. Simplified lti.js - now simple one function.
Updated tests.
Fixing Jasmine tests.
Acceptance test for LTI module (not finished), but working
Adds oauth checking to acceptance tests
updates
acceptance tests updated
updates for acceptance tests
updated comment
added roles and student id
custom parameters
updated docs
Add course setings for client key, secret
Add documentation to LTI module and to dev docs
Updated error message in LTI template.
Improve LTI module

Add simplifyed template.
Update lti integration test.
Add getting oauth credentials from course settings.
Add user id transferring to provider.
Improve documentation of lti module.
Pass user_id and course_id to runtime in cms (dev) and tests.
Update docs.