This looks pretty cool, and I'd love to give it try, but I don't see any license mentioned. Have you considered any license yet?
I've settled on GNU GPL v3. Thanks for the catch. :)
I'd like to politely suggest you consider changing the license before you accept contributions. The smaller the tool and the more modularity it has within a software stack (shell script helpers are extremely modular) the more appropriate it is to license it something towards the MIT license end of the strong - weak copyleft spectrum.