Resurrection of whiteknight's eval_pmc branch

[Patrick R. Michaud]

On Sun, Feb 17, 2013 at 05:32:14PM +0100, Gerhard R. wrote:
> I now added a --target=pbc frontend to both NQP and Rakudo (see
> https://github.com/rakudo/rakudo/pull/102 ) so a two-step build
> process of modules is no longer necessary.

Also, out of curiosity, does going straight to .pbc slow down 
the build process significantly?  I can imagine things being
slower because the pir->pbc step would now be running when there
are a lot of GC-ables left over from the parse/codegen phases.

This isn't necessarily a blocker, but it's something we ought
to check.

Pm