Comply with best practices, Round 2

| Q   | A
| --- | ---
| Doc fix? | yes
| New docs? | no
| Applies to | all
| Fixed tickets | partly #4431 

Less other fixes, more find/replace this time to speed up the process. I have one question this time:

* Should we just mention the use of the param converter (the current case), or update all simple controller examples to the use param converter?
the Symfony standard is to always use `===`