* improve single page website tracking

* added docs and minified piwik

* Re-generate piwik.js

Cross Domain: forward pk_vid parameter when the clicked element is not directly a link but is within the link <a> element itself (#11262)

* some work on tracking cross domain

* fix some bugs

* fix some edge cases

* fixed tests and added more new tests

* we also need a device specific id to avoid when time is not correct on a different computer etc

* more tests

* minified piwikjs

* use only one parameter and validate values

* fix tests

* improve code

* Re-generated piwik.js

* UI Test

* Comments

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

* Fix jslint

* refs #11023 better piwik.js json compatibility

* fix some tests

* fix json lint tests

* expose JSON property for Piwik custom trackers

* added test

Piwik JavaScript tracker: we now track by default Downloads and Outlinks when user clicks on the mouse right button or the mouse middle button 

* track a unique id for each pageview

* fix tests

* reduce idpageview to 6 bytes

* added changelog entry

refs #6106

piwik.js: Prepend a slash to all paths such as when users don't specify leading slash for URL path (#10302)

 #10271 #10105

* Do not add current domain automatically if setDomains is called, might also fix a bug in IE11

* this might fix jslint test

* added tests and fixed a bug

* fix tests

* Up to date piwik.js

* Minor changes

* Clarify that token_auth must be  an admin or super user token.

* Reset the list of items in the cart, after tracking an ecommerce conversion

But do not reset the list of itms in the cart after tracking an ecommerce cart update.
fixes #10252

* Adding changelog note
`piwik.js`: after an ecommerce order is tracked using `trackEcommerceOrder`, the items in the cart will now be removed from the JavaScript object. Calling `trackEcommerceCartUpdate` will not remove the items in the cart.

JavaScript SDK: add support to send tracking requests to multiple Piwik servers and/or store in one or  multiple websites ID (#10085)

* Add support to configure multiple trackers easily

* added tests

* fix tests

fixes #9924 outlinks and downloads are not tracked if document is already ready when piwik.js is loaded

Instead, we will better document how to correctly set the cookie configuration. https://github.com/piwik/piwik/issues/9932