apple-gcc42 is now in homebrew/dupes
Update rvm install command

1. Prefer homebrew (otherwise macports gets used if installed)
2. It seems that the command has been updated to `\curl -sSL` instead of `curl -L` for clearly specific reasons.
Merge pull request #2390 from devinrhode2/patch-1

apple-gcc42 is now in homebrew/dupes
Merge pull request #2391 from devinrhode2/patch-2

Update rvm install command