Pour les exercise_report
Merge pull request #217 from baelmyhu/1.9.x

Adding advanced CSS personalization for Learning Path -ref #6976
Merge pull request #218 from baelmyhu/1.9.x

Bug correction, allow platform's student to see courselog of courses they are admin
Removing console.log.
Adding missing <html> tag.
Format code + adding require in order to load constants.
Merge branch '1.9.x' of ssh://github.com/chamilo/chamilo-lms into chamilo19
Format code fixing PHP warnings
Adding GROUP_USER_PERMISSION_PENDING_INVITATION as an option see BT#7156
Fixing query BT#7156
 Roberto González fix for BT#7413
Adding x-sendfile header see #6853
Fixing PHP notices.
Minor - fixing PHP notice.
Add installation guide section for Sendfile header - refs BT#6853
Merge remote-tracking branch 'origin/1.9.x' into 1.9.x
Merge remote branch 'upstream/1.9.x' into exercise_report
Clean all results for this test before the selected date -ref #6970