make: Add rule for running nosetests

Signed-off-by: Anton Lofgren <alofgren@op5.com>
tests: Add simple test to check that we populate the root as expected

Signed-off-by: Anton Lofgren <alofgren@op5.com>
README: add test dependencies

Signed-off-by: Anton Lofgren <alofgren@op5.com>