Print status at job end from CLI

Hadoop 2.2.0 does not provide any output that can be reliably be used to
determine the success of the job. Instead, check the exit code of the
hadoop command.
Refactor status filter spec
Add status filtering support for Hadoop 2.2.0

Support for 1.0.3 is still there.
Move to the modern convention of (ignored) .ruby-* files instead of .rvmrc
Merge branch '220-status-filter'
Move extra hadoop args to launch options
Make EC2 key name an option
Parametrize hadoop_version and aws_region
Implement `humboldt configure`

The structure of Thor did not allow the configuration file values to be
injected into options with higher priority than the default, but lower
priority than the command line arguments. Therefor, the default
functionality of Thor is no longer used.

`humboldt configure` will create a .humboldt.yml file in the current
directory, and provides a simple interface to set some defaults.
Remove Burt specific default buckets

Set these via `humboldt configure`
Add integration test for config file reading

This is not perfect, but will at least cover that the configuration file
is actually read and considered when running humboldt.