Merge branch 'hotfix/1.21.9'
fix checksums for centos yaml installation, fix #2030, update 51a8b7a57ff30ef88e622ff21701b8dcbabe0bed
remove tgz and fix gitignore to prevent it, update 06852b7b44074a3e3d66a3c93da8efc15f925323
reworked checking if bundler is in context of rvm, update #2031
Detect path to MacPorts installation, don't use hardcoded /opt/local
Merge pull request #2034 from crystax/master

Slight fix allowing rvm work on OS X even if MacPorts where installed to custom path
cleaning macports root check, update #2034
make sure any ree* string is recognized as ree, update #2035
improve homebrew package installation error, fix #2035
add monthly as rubinius patch level, notify @brixen
simplify rbx remote rubies listing, thx @brixen
1.21.10
Merge branch 'master' into hotfix/1.21.10
Merge branch 'hotfix/1.21.10' into stable