Migration guide

[KroArtem]

It'd be very handy to have a migration guide from HtmlElements2. Maybe in a form of a small wiki-page or as a part of readme.

[KroArtem]

Some things I didn't manage (yet) to find.

1. How to write your own extensions (htmlelements way vs. atlas way). Do I need to implement MethodExtension?
2. ElementsCollection doesn't seem to have convert method that was quite useful.

[artsok]

First point,

1. Yes, you need to implement MethodExtension

2. How we can to override behavior of a click

3. Set our extension to Atlas

Secont point,
You can try instead of 'convert' this way collection.stream().map(it -> it...).

[KroArtem]

JFYI, first version of guide was here: https://github.com/KroArtem/atlas/wiki/Migration-guide

Right now it's waiting for other tasks.