Also the get_property_definition() was created to get the property without retrieve the whole definition cache and
unit tests were created to tests those new methods.
With fake noreply and support users, the notifications were not accessible by user
Support for viewing messages from noreply user has been added.
Signed-off-by: Rajesh Taneja <rajesh@moodle.com>
This is used by messaging system for sending/receiving message
to/from noreply or support user. message_send api will now use
core_user class to get noreply or support user and then
send/receive message depending on user state.
