Remove the responsibility for loging the application of the course start date offset, from activity modules to the backup module.
Merged from stable branch
* Add fields to restore form to enable changes to Short Name, Full Name and Start Date
* Start Date offset added to Restore process
* Created Restorelog file in Course files area
* Activity Modules use offset to change dates
* Activity Modules write changes to Restorelog
Added new function, import_backup_file_silently
Changed everything that prints stuff to check for a constant first.
Backup_flush checks a different constant, this is so that output can still
get flushed to the browser when necessary but not print <li>s everywhere.
Please test this!
This patch allows the much requested selection of individual instances of modules within a course to backup and restore.
It needs A LOT of testing and probably some prettyifying too.
by Ray Kingdon.
Works quite well, but it's not clear yet if this will be part of
major releases (due to the overlap with assignments and workshops
and the confusion this may cause).
