SecondPort

Results 3 issues of SecondPort

Fixes #3599 #### PR Checklist - [x] Tests - [x] Documentation - [x] Changelog entry (It's my first PR contributed to open source)

I think the correct solution to this security error was to add a validation step that rejects user names with certain characters, I hope this is the correct solution and...

- Relax material constraints in is_material_reachable function - Allow reaching any material configuration through captures and promotions - Fixes issue with reference database not showing options after pawn promotion Related...