Merge branch 'hotfix/1.22.3' into stable
Fix syntax error in migrate script

```
migrate: line 98: syntax error near unexpected token `fi'
```
Merge pull request #2195 from felixbuenemann/fix-migrate

Fix syntax error in migrate script
formating ifs in migrate, update #2195
clean setting source and destination ruby in migrate, update 2195
Make _system_name_lowercase available for unknown systems. Some code clean-up
Merge pull request #2196 from Ch00k/master

Make _system_name_lowercase available for unknown systems. Some code cleanup
fix checking for fallback url after the ruby url change, update #2136, fix #2197
Merge branch 'master' of github.com:wayneeseguin/rvm
extend checking for fallback urls, fix the 'rvm tools mirror' command, update #2136, update #2197
1.22.4
Merge branch 'master' into hotfix/1.22.4
Merge branch 'hotfix/1.22.4' into stable
Merge branch 'hotfix/1.22.4'
manually reverted using mirror site. and use https protocols
use http, because http://ftp.ruby-lang.org is deliveried by fastly
rename hostname, ftp.ruby-lang.org is used by ftp protocol too.
add the missing __rvm_stat, update wayneeseguin/rvm-capistrano#93
Merge pull request #2198 from hsbt/revert-using-mirror

Manually reverted using mirror site. and use CDN serves.
allow easy defining multiple fallbacks for ruby, update #2198