add. tox.ini for nosetests and pep8 compliance.  unit testing methods.
add. docs for src.utils modules.
fix. moved default methods into aggregator defs.  Pep8
rm. DataFilter and ExperimentsLoader no longer exist.
add. median aggregator
add. register median aggregator with bytes_added.
add. docs for metrics_manager module. pep8.
mod. generalize median aggregator to any numpy op that may operate on numpy arrays.
mod. rework bytes added median aggregator to use generalized aggregator def.
add. builder method for aggregator numpy_op functions
add. min/max aggregators for bytes_added
add. median/min/max aggregators for edit_rate
add. kwarg that allows data conversion type to vary in numpy_op
mod. added data_type kwarg to edit_rate aggregators.  PEP8
fix. pep8
add. rate aggregator for blocks. pep8.
rm. identity method.  obsolete.
add. AggregatorMeta type.  This, combined with changes in numpy_op, allow greater flexibility in building aggregator methods from numpy_op.
mod. refactored edit_rate and bytes_added to work with AggregatorMeta
rm. module moved to query sub-path and renamed.