Upgrades rubygems for 1.9.1: 1.3.5 -> 1.3.7
fix exit status of install with verbose
Rename the CAfile to cert.pem since that's the hardcoded default.

$ strings ~/.rbenv/versions/2.0.0-rc2/openssl/lib/libcrypto.a |
  grep -B3 SSL_CERT_FILE
/Users/jeremy/.rbenv/versions/2.0.0-rc2/openssl/ssl/certs
/Users/jeremy/.rbenv/versions/2.0.0-rc2/openssl/ssl/cert.pem
SSL_CERT_DIR
SSL_CERT_FILE
No need to rehash when using CAfile. Used for file-per-cert CApath hashing.
bump versions to 2.1.0
Merge pull request #313 from hsbt/bump-versions-210

bump versions to 2.1.0
Merge pull request #310 from znz/fix-exit-status-of-install-with-verbose

fix exit status of install with verbose
ruby-build 20130225
Build a shared openssl to link to Ruby as a stopgap to fix build issues some people are having, pending understanding why static linking isn't working.
ruby-build 20130226
Default Ruby CFLAGS to `-Wno-error=shorten-64-to-32`; don't set `CC`

Ref. #290, #311
Feature detection for `-Wno-error=shorten-64-to-32`
Merge pull request #252 from jessedearing/upgrade_191_rubygems

Upgrades rubygems for 1.9.1: 1.3.5 -> 1.3.7
ruby-build 20130227
use --continue when downloading tarball
keep source tarball if '--keep' or 'tar xf' fails
`rbenv install 1.9.3` lists matching definitions
Merge pull request #326 from quark-zju/keep-downloaded-tarball

Keep downloaded tarball sometimes
add jruby-1.7.4-dev
Updated README.md to use https to clone ruby-build