Perhaps actually raise an error if extra configuration is broken
Use option_merge for images and pass around less

Using option_merge to join together the heirarchy of options for each
image

Also put all options into the configuration rather than passing around
arbitrary options

As part of this, I also moved some functionality out of harpoon.tasks
into harpoon.option_spec.objs

I also made image.commands lazily evaluated to cut down startup time
Making harpoon work with docker 1.3
Complain about missing environment variables early
Fixing the push_all task
Image doesn't have heira_formatted anymore
Upgrading dockerpty
Version bump

* Now works with docker1.3
* Using new input_algorithms
* Fixes #10 (thanks dockerpty)