Correction for direct course login, see git comment

https://github.com/chamilo/chamilo-lms/commit/301fb962da7eb87ddb8eff15deee92804228fda1#commitcomment-5835012
Correct add link in assessement that appear twice - ref #6602
Coding convention
Add option to hide group's forum in main forum tool -ref #6724
Fill survey from email URL with code works with CAS enbled -ref #6875
Add coding convention
Merge pull request #254 from baelmyhu/1.9.x

Merge for several tasks