[docs]: Explain differences with ide-helper and how to make both coexist.

[mathieutu]

Feature Description

Hi,
As this plugin does not execute any PHP, I have wrong autocompletion if any logic is used (for example in casts method).
The ide-helper package can help for that.
However, we don't know how much it's compatible or conflictual with this plugin, and to make them both coexist the most as possible.
I think it could be good to add something about that in the doc.

Thanks,
Mathieu

[adelf]

There are no issues. Maybe some duplicate completions sometimes... Nothing really annoying. That's why it isn't covered in the docs.