CourseProgress v2, tracks-add

. Tracks being added
. tracks-add's layout fixed
. Started working with quizzes

- TABLES CREATED: tracks_enrollment, track_content

- MODELS CREATED: tracks_enrollment, track_content
- MODELS UPDATED: tracks, course
CourseProgress v2, tracks-add, db updated

.Tracks being added
.Tracks-add's layout fixed
.Started working with quizes

- TABLES CREATED: tracks_enrollment, track_content

- MODELS CREATED: tracks_enrollment, track_content
- MODELS UPDATED: tracks, course