Don't set the Rubinius gems directory to the prefix

This causes tricky issues with Bundler. Bundler assumes that the
configure gem path *only* contains gems. When using this configuration
option, this is not the case.

What happens is that Bundler then removes the path for the Ruby stdlib
from the load path, because it is located inside what is configured as
the gems directory. This then breaks for example Rails applications when
using ruby-build to build Rubinius.

Also see: https://github.com/rubinius/rubinius/issues/2544

Homebrew homepage location changed

Change server protocol of the ruby-lang.org server in the MRI definitions from HTTP to FTP

Closes #375.

use Homebrew openssl if available

Fixes #343, references #367

making checksum comparison case insensitive

Add install script for Maglev 2.0.0 dev (the branch with 1.9 support)

Fix the has_broken_mac_openssl function for the pre-release version of OS X

Treat the openssl 0.9.8(r|x) bundled with OS X as broken library. So the ruby-build will download and build the latest one.

Added JRuby 1.7.4

Replaced 1.9.3-p426 with 1.9.3-p429 definition (p426 was yanked after release due to build issues)

1.9.3-p426 was deprecated by 1.9.3-p429 since it won't build on RHEL6
systems (and others?)

added 1.9.3-p426 and 2.0.0-p195

Allow define RUBY_CONFIGURE_OPTS on rbx configure

The configure of rbx can take a RUBY_CONFIGURE_OPTS. You can by example
use the `--skip-prebuilt` OPTS

Restore -O3 default when we build with clang

Unable to clone ruby-build from behind firewall

Fixes #267

Fixes `rbenv install` in a directory with a .ruby-version file that specifies ree