Added support for adding plugins in Tracker public API
Fixed addPlugin unit test to use a different approch for verifying custom plugin was succssfully registered and works as expected
Merge pull request #336 from sslavic/tracker_addPlugin

[piwik-js] Added support for registering plugins in Tracker public API fixes #5393
add comment to function refs #5393
refs https://github.com/piwik/piwik/pull/336
Fixes #5388 throw exception if date is not valid
UI Notifications link moved to User menu
Fixes #5356 Applying change suggested in pull request https://github.com/piwik/piwik/pull/320
(the only change was to set default timezone to UTC)
beta9
Create piwik.zip symlink during build time
factor out code in method processArchiveDays()
factor out more code to method processArchiveDays()
core:archive console command: new parameter --force-periods
refs https://github.com/piwik/piwik/pull/319
refs #5396
fix bug in --force-periods logic
refs https://github.com/piwik/piwik/pull/319
refs #5396
Add support for --force-date-range parameter + also enable Verbose logging via -v
refs https://github.com/piwik/piwik/pull/319
refs #5396
fix output logging when --force-date-range is used
refs https://github.com/piwik/piwik/pull/319
refs #5396
add --concurrent-requests-per-website: When processing a website and its segments, number of requests to process in parallel
refs https://github.com/piwik/piwik/pull/319
refs #5396
Minor params re-order