Enabling anonymous surveys -refs #6829
Protecting survey preview page -refs #6829
Protecting survey preview page -refs #6829
Protecting survey preview page
Indentation
security added
code conventions
Added information about the implementation of the X-SendFile module - refs #6853
Minor - formatting code, fixing PHP warnings.
Minor - format code.
Cleaning wiki code see #7006

Moving code inside a class, using session to handle messages,
replacing relative to absolute image paths, fixing redirections.
Merge branch '1.9.x' of ssh://github.com/chamilo/chamilo-lms into chamilo19
Merge pull request #166 from ycastillo/6829.new

refs #6829
Minor - fixes PHP warnings.
Fixing multiple true/false/doubt question see BT#7780
Minor - format code.
Minor fixing delete hotpotatoes where there are any contents.
Fixing hotpotatoe error when folder is empty.
Merge branch '1.9.x' of ssh://github.com/chamilo/chamilo-lms into chamilo19
Adding missing default_scorm.css.