Add new Custom Segments: outlinkURL and downloadUrl to segment on any Clicked URL or Downloaded file

Segment subquery cache: minor code review items

https://github.com/piwik/piwik/issues/8850

Conflicts:
	plugins/Live/stylesheets/live.less

Fix some icon placement issues

Minor css fix and improvements for sparklines

Small UI fix for GeoIP admin

Do not use eval in minified piwik.js, replace JSON2 with JSON3

Make sure plugin environment files are loaded after the base environment config file instead of before w/ the plugin's config.php file.

Do not manually include fixture files during tests so one plugin can't break tests of another

Make sure plugin environment files are loaded after the base environment config file instead of before w/ the plugin config.php.

Doing it the old way causes plugin environment specifc config to be unset by the core environment config (eg, a plugins' test.php will have no effect, because core/config/test.php ends up overriding it).

Since autoloading is used now, do not manually include fixture files during tests. Fixes case when one plugin has issue in fixture class making it impossible to run tests (since the tests:run will just fail).

Regression: columns query parameter is never urldecoded in PHP so it cannot be encoded in JS.

Clicking too fast can result in nothingness

Disable save button when clicking on it

Auto generated glossary of all Metrics & Report definitions in Piwik 

UI tests: New API for Glossary + link to glossary on Help page https://github.com/piwik/piwik/issues/6773

Do not fail bulk tracking request if individual request has an incorrect request parameter.