Added PHP-DI + StaticContainer class
The FrontController now uses the container to create controllers (i.e. DI in controllers)
Injection of dependencies through annotations in controllers
Use ArrayCache for now
Replaced calls to $container->get() to $container->make() for controllers, makes sense since controllers are not services
Use version 5.0.x-dev for PHP-DI
Merge branch 'master' into php-di

Conflicts:
	composer.json
	composer.lock
Updated PHP-DI dependency
#5052 IP anonymisation enabled by default, users can disable it during installation
Changed some wording
#6579 and #5052 Anonymize IP addresses on 2 bytes by default
Added legal notice for PHP-DI
Merge branch 'master' into php-di
Merge branch 'master' into installation_privacy_options
#5052 Enabled IP anonymization by default. To keep it disabled on previous Piwik installs, a migration script disable it on upgrade to 2.9.
#5052 #6566 Added a form on the last installation step that plugins can enrich

The PrivacyManager plugins adds 2 settings to that form to let user disable (enabled by default) DoNotTrack and IP anonymization
Fixed tests
Use placeholders in translations
added missing single quote
refs #6429 clean submodules before fetching any data [skip-ci]