Fix failing test
Remove test :focus
Handle error codes for short lived scripts
Trap Errno::ENOENT
Wrap "naked" commands in a script before executing them with PTY.spawn
Ensure script is executable
ignore Errno:EIO when running scripts on *nix
Merge pull request #21 from mrdavidlaing/master

Beef up execution of "naked commands" by wrapping them in a script.