[DI] Service subscribers#9223

Merged

wouterj merged 3 commits intosymfony:3.4from

codedmonkey:fix_7740

Apr 18, 2018

Commits on Feb 16, 2018

Refactor service locators article to primarily describe service subscribers
codedmonkey
committed

Commits on Feb 28, 2018

Minor tweaks to service subscribers article
codedmonkey
committed

Commits on Apr 18, 2018

Incorporate feedback
codedmonkey
committed