Outdated information in Interaction guide

[luxaritas]

I noticed a couple of issues on https://pixijs.io/guides/basics/interaction.html I may be able to submit a PR to improve this at some point, but wanted to at least make a note:

• Code examples still use Interaction, not EventSystem
• The section on pointer events suggests using non-pointer events "to support different modes of operation based on input type or to support multi-touch interaction". Pointer events should allow for both use cases, via pointerType and pointerId, respectively.
• The caveats about not supporting bubbling and capturing are no longer accurate (thanks to EventSystem)

[bigtimebuddy]

PR would be awesome! Thanks for pointing this out.

[dreadwail]

@luxaritas Another thing I noticed from that page that maybe you'd want to include a fix for in your PR: The buttonMode property is in the code examples despite having been removed in v7.