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.
Apparently not in the way that I am using it. Removing either the `-I` or the `-L` results in a configure error.

    configure: error: C compiler cannot create executables

The brew ENV shows `LDFLAGS` and `CFLAGS` without the `-{I,L}`