rjsf version 2 support

[Morriz]

Hi, rjsf v2 is out for over a year now, and I just wasted quite some time trying this lib because it does NOT say it is NOT working with v2. We use v2 since it came out, and I assume most ppl are using it.

Do you have plans to migrate to v2?

Otherwise, Would you please update your docs? I suggest a mention in the top of the readme so others can avoid wasting cycles trying to get this to work.