Added pure ES6 class and changed 4 things

[kristofzerbe]

Due to my needs, I ported bouncer to a separate ES6 class and did following feature changes:

• Custom Messages for all types
• Introduced targets
• Extended validateAll() argument
• Introduced settings.errorTag

[cferdinandi]

Thanks for this. Bouncer is in need of an update for sure.

I have a new design pattern I'm using, and will likely port many of these updates into the rewrite at some point. Keeping this open and unmerged for a bit as I plan next steps.

[kristofzerbe]

👍