Access Control Plugin #2697

Description

This plugin implements an access control layer for Piwik users. It makes sharing only parts of reports with different users possible. The restrictions are based on labels and metric names.

Implementation

There are only a few adjustments to core needed. The rest will be made available as a third party plugin.

(In [5286]) refs #2697 parent reference can be archived with nested datatables

(In [5287]) refs #2697 plugins can manipulate api output using the hook API.Proxy.processReturnValue

In [5286], I also committed the new method DataTable::getEmptyClone. It's needed for another ticket I'm working on, but why not review now ;-)

Speaking of review, please have a look at the changes.

Looks good, however it's missing some unit tests in datatable.test.php - maybe one test function to check that all methods copying/creating tables have the parents array?

In [5287] what is the reasonning when testing for Piwik_*_API class name?

What happened to this plugin btw?

In bead696cfe7a678a9b0d3ea57f98748709eefbb8: Removing feature: enable_archive_parents_of_datatable = 0 (main reason: there is no test, second reason: there is no public plugin using this feature AFAIK)
@Timo if you need this feature, let's put it back with some tests..
Refs #2697