Numerous Course Validation Script Updates

- Added support for basic auth
- Logging into LMS (instead of using auto-auth)
- Added support for multiprocessing (runtime is down to 5 minutes from 25!)
- Retrieving courses from Insights homepage
- Logging to both console and file
- Writing CSV upon process failure

@rocha @dsjen 
Still, I do not like the idea of hardcoding values like this one into the codebase, even if they are tests. We may start relaying on them on the test caller, which then creates a mess when things change.