* fix #11512 Premium Plugin Installer shows false error message after install

* better handling when a plugin was installed

* New event that lets plugins trigger notifications in the admin area

They have to be triggered before assigning the notifications to the view and there is no other way to determine when a plugin is supposed to trigger notifications in the admin. Ideally, in the future we would even move the notifications above to CoreAdminHome or somewhere else eventually.

First thought of using `Controller.addAdminNotifications` as we often use this wording but then we would need to rather do `Piwik::postEvent('Controller.triggerAdminNotifications', &$notifications);` as otherwise nothing can be added.

Plugins could actually also use this event to cancel notifications where in the past it was needed to hide them via CSS. 

Happy about any other naming suggestions but want to keep it "specific" to notifications and not something to general like `postEvent('Controller.renderAdminView, $view')`.

* document new event

See http://us2.php.net/manual/en/function.random-int.php : random_int — Generates cryptographically secure pseudo-random integers

https://piwik.org/changelog/piwik-3-0-2/

* Post new parameter with conversion event

* also added new method to get a specific custom field

Need this method in a plugin.

* Fix UI test error

* UI tests after fixing number of activated plugins

* Do not count always activated plugins.
Fixes #11144

* UI test: Fixed count of activated plugins

Similar to https://github.com/piwik/piwik/pull/10887 makes sure the rate metrics are formatted in mobile app. I wonder if we should maybe simply change it to `'/.*_rate$/'` and then remove several of them? Would simplify it for the future and be faster

New "Enable cross domain linking" checkbox in Javascript Tracker Code generator (Advanced section) (#11295)

* enable set domains when enable cross domains

* fix disable cross domain when only one site url or less

* New "Enable cross domain linking" checkbox in Javascript Tracker Code generator (Advanced section)

* Integration test

* API has new parameter

* Cross Domain: forward pk_vid parameter when the clicked element is not directly a link but is within the link <a> element itself

* Add custom commands when Piwik is not installed yet

* Use config file to define Plugin names

* minor

* clean code

Email reports in HTML: Updated styling to be consistent with new Custom Alerts emails design  (#11251)

* Updated Email Report/Downloaded Report. Added new styling found in the Alert Email. i.e navigation bar uptop, styled tables, added powered by piwik footer. Note: "back to top" link only works on downloaded version, not on the email.

* Fixed the back to top link not working in emails.

* Fixed a bug where logo was not centered in gmail

* Translations

* Code cleanup and making PDF generation work

* removed htaccess

* fix unit test

* Some test fixes

* UI Test

* Fixes #11197

The 'while' loop was causing a memory leak, replaced with an 'if' to match the correct functionality.

* Removed blank lines.

* Add back while loop and added an extra condition to prevent infinite loop.

* fixes #2321 when tracking request is > 2000 char, prefer POST

* Fix jslint

* Change to gender neutral phrasing in user-facing text

* Switch to gender neutral wording in docs/comments