This PR aims to fix #7444 and adds the possibility to exclude an extension from the list of "download extensions".
It also converts the list of already excluded extensions into an array and resolves the regexes to single values, so it is possible to remove only some of them.
Methods for setting, adding and removing extensions now accept single values as well as multiple values (as array or separated by "|")
I've added some tests.
looks good to me, merging :+1:
Sorry. I somehow thought the documentation is some kind of autogenerated. I've updated the doc in https://github.com/piwik/developer-documentation/commit/1794b90a2f8b95b2aef0812bfeaf66811a64edac