Fix/namespace discrepancy

[irinahpe]

Add consistent namespaces with mod_ratingallocate on level1.

Closes #292

[FelixDiLenarda]

The incorrect namespace designations lead to the failure of the ad_hoc task with the following output:

Execute adhoc task: mod_ratingallocate\task\distribute_unallocated_task
Adhoc task id: 90667432
Adhoc task custom data: {"courseid":"38278","cmid":"1786341","distributionalgorithm":"distribute_unallocated_equally"}
... started 12:13:03. Current memory use 42.6 MB.
Debugging increased temporarily due to faildelay of 7680
... used 1 dbqueries
... used 0.00084400177001953 seconds
Adhoc task failed: mod_ratingallocate\task\distribute_unallocated_task,Undefined constant "mod_ratingallocate\task\ACTION_DISTRIBUTE_UNALLOCATED_EQUALLY"
Backtrace:
* line 508 of /lib/classes/cron.php: call to mod_ratingallocate\task\distribute_unallocated_task->execute()
* line 302 of /lib/classes/cron.php: call to core\cron::run_inner_adhoc_task()
* line 128 of /lib/classes/cron.php: call to core\cron::run_adhoc_tasks()
* line 186 of /admin/cli/cron.php: call to core\cron::run_main_process()

This PR fixes the Issue.
The integration of the pull request is therefore eagerly anticipated. :)

[PhMemmel]

I think the issue already should be have been fixed by #294, however correct namespaces are always a good idea :)

[FelixDiLenarda]

Even better :) Apologies for the fuss.

[Laur0r]

Thank you for fixing the namespaces!