with-readline 0.1.1 (new formula)

Adds a formula for with-readline which adds readline support to tools
that don't have readline support like the OSX native sftp.

This depends on readline and fooling about with {C,LD}FLAGS was the
way I figured out to make this build. Criticism appreciated.
This test actually fails silently:
> ==> /usr/local/Cellar/with-readline/0.1.1/bin/echo 'exit' | with-readline expect
sh: /usr/local/Cellar/with-readline/0.1.1/bin/echo: No such file or directory

You can write this as `system "echo 'exit' | #{bin}/with-readline /usr/bin/expect"`