RFC: Move build tools to Perl5, developer tools to Perl6

[Jimmy Zhuo]

> Hello.

> Moving opsc back to perl5 is the biggest mistake you can make. Upgrade
opsc
> to modern nqp is the way.

> Keywords: JIT, compile-time optimisations, PBC emitting, kill PIR with
fire.

> -- 
> Bacek

I'm not optimistic about JIT, since parrot's ops is so easy to extend.
Java/Lua VM can't JIT well too if we can easily add some new ops, me thinks.
I'd like to see jit m0.
---
Jimmy Zhuo