Building trunk hotspot-comp

[Charles Oliver Nutter]

I've posted a gist with a script and instructions for setting up a
trunk build environment for the Hotspot compiler team's branch:

https://gist.github.com/1148321

Hotspot guys: let me know if anything else needs to be tweaked here.
It works for me, and it's surprisingly easy to build.

I'll also try to periodically post builds with in-flight patches like
the recent invokedynamic optimizations. For now the i586 build (with
everything 292-related up through Christian's inlining discount patch)
is available at http://jruby.org/jdk.

Linux only right now. I wish bsd-port would get merged in!

- Charlie