Cleaning FormValditor class, allowing forms with no name (using unique id)
Removing Fckeditor see #5875
Using formvalidator instead of <form>.
Removing old Fckeditor code and using the Editor class see #5875
Undo change html_filter functions are needed when using filters.
Removing unused calendar.lib.php file.
Minor - fixing UI, format code.
Using formvalidator helper in order to add users/groups see #6854
Removing unused functions, moving functions in the agenda.lib class.
Removing fck classes calls see #5875