Merge branch 'hotfix/1.23.10'
move sourcing to one place in installer
add a message to run installer with rvmsudo to fix permissions problem, closes #2300
fix creting temporary file for bashrc, cleaneaning code, fix #2304
assume true no matter if something was removed from /etc/bashrc or not, update #2304
on older osx / brew select apple_gcc42, fix #2303
autodetect short rubinius versions, fix #2303
introduce selector_late and move rubinius version detection code earlier so it can be used for checking binary rubies, update #2302
add lib type debug output, update #2305
move the stderr to stdout, update #2305
fix checking compiler, require installing apple-gcc42 when using macports only for ruby-1*, fix #2305
improve checking if compiler is clang, update #2305
fix detecting shell sourcing source when in Zsh, fix #2306
adding jruby-1.7.6 release