Use version 1.8 of ruby for bundle items

10.7 and 10.8 only include ruby 1.8, so all bundle items have been written to work with that. Optionally supporting ruby 1.9 and 2.0 is problematic as these versions are not fully backwards compatible.

#ignore
Add sh/bash/zsh shebang line snippets (sh/bash/zsh⇥)

This is usable in any document provided the trigger is at the very start of the document.
Change shell shebang to call /bin/sh directly

This should be standard on all systems.
Send 'clear' after cd'ing to dir in Open Terminal command.
Make 'Open Terminal' open a new terminal tab.
Remove keybinding for 'Execute Line and Replace With Result'.

We use ^R for RSpec (run in terminal), instead.