MDL-31356: Feature addition to IMS Enterprise Enrol plugin

Removed unused, commented out code

Only send email if we attempted to process a file, otherwise this
will send email every time the cron job runs which is typically every 5
minutes.

Feature 1: Allow nested categories when creating courses.
Feature 2: Allow updates to course Full Name, Short Name, and Description.
Feature 3: Allow setting authentication type for users.
Feature 4: Allow updates to users.

Added test functions.

Fix to course update routines so it doesn't muck with DB directly.
Merge branch 'MDL-31356' of github.com:perlwiz/moodle into MDL-31356