refs #5940 put tests in correct folders, better testsuite names, some tests still fail and I cannot figure out why

This is only a start. Especially the Tracker model contains quite a bunch of different models. Ideally, one day, the tracker is refactored and all the goal tracker stuff including the queries are in the goal plugins, all the ecommerce stuff is in an ecommerce plugin etc. Haven't moved some of the LogAggregator queries.

Extracted the decompressing classes into a standalone component

Refs  #6224 check for HHVM first to avoid it picked up by the isValidPhpType call @voidswitch Does this fix the issue for you?

Optimize DatabaseTestCase by creating DB and tables only once (like IntegrationTestCase) so travis build will be faster.

Refs #6342, give all commands superuser access by default (since any user that can execute a command can do more than a superuser already).

Refactor DbHelper::truncateAllTables() to truncate non-core tables, and tweaks to DatabaseTestCase tests.

Use an angularjs directive to create Piwik notifications. The old class still remains since notification placement is out of scope for the notification directive.

Fixes #6313 - When a user starts to get a User ID set, then we set this User ID to the existing visit rather than create a new visit for this user id specifically

Refs #6313 Adding test case showing the bug (it creates a new visit but we want this visit to be re-used)

Fixes #6314 do not display error Warning: shell_exec() [function.shell-exec]: Unable to execute 'stat -f -c "%T" /proc 2>/dev/null