Definitions for jruby-dev, ruby-trunk and update for rbx-dev

Install jruby-launcher after of install JRuby

Support REE 1.8.6

Support REE 1.8.7-2010.02

set --with-gcc=gcc-4.2 on lion + xcode 4.1

Include --with-gcc config flag for gcc-4.2 on Lion, per https://github.com/ruby/ruby/commit/9151ed22b360ba3d2bde3b51969a682f9a4a3096

Add install_git and refactor to support it. Pass package name, git url, git ref, and build commands.

rbenv-install

This reverts commit 20f7b5c0.

Conflicts:

	bin/ruby-build

REE should use the do not install helpful gems option

no need to start with a bunch of cruft we may not even be wanting to use, let users install their gems themselves

Add definition for jruby-1.6.4

Could you add this definition to ruby-build ? Thanks!