Proposal: Make the c# language ready for lop

[furesoft]

hi, i found this project:https://github.com/xs-admin/Excess
its really cool. so why not make c# extensible with custom syntax?

[HaloFour]

If any syntax could be legal syntax that would severely impede the team from being able to further evolve the language without causing breaking changes.

[Joe4evr]

See also the discussion at #83.