Add support for `RUBY_CONFIGURE_OPTS` and `RUBY_MAKE_OPTS`

These variables let you pass Ruby-specific configure and make options
that will not be passed to dependent packages like libyaml.
Build OpenSSL for Ruby 2.0 on OS X.

Apple ships a patched, incompatible OpenSSL. We build a compatible
OpenSSL from source.
Add PACKAGE_{CONFIGURE,MAKE}_OPTS_ARRAY for injecting quoted arguments
Extract `package_option` helper
Default CC=cc for broken Ruby 2.0 gcc detection on OS X
Quote `$PREFIX_PATH`
We use `uname -s` to test for OS X elsewhere; stay consistent
Guard against missing openssl (future OS X versions?)
Handle 32-bit OS X
Remove OpenSSL note in the readme
Explicitly declare OpenSSL condition and URL in the definition files
Add 1.9.3-p385
Merge pull request #277 from sorah/193p385

Add 1.9.3-p385
Update examples to use latest MRI
ruby-build 20130206
Add 2.0.0-rc2
Merge pull request #279 from lucasuyezu/master

Add 2.0.0-rc2
Merge master
Use $RUBY_BIN
Be sure to use c_rehash from the OpenSSL build we just installed