Add user statistics app to Langstroth

Removed imports from __init__.py in test modules to keep
Flake8 happy. These empty files are needed by the PyDev
test runner to locate test modules.
Removed blank lines at end of file.
Added dependency for jshint.
Addressed most, not all, jshint complaints.
Test fixed. Array order was unstable,
 so it's now sorted for assertion.
Additions to readme file for Py.test in Eclipse.
Changed to use Graphite instead of database.
Reapplied flake8 rules.
Changes to settings files to be consistent with debian packaging.
(not working yet)
Applied flake8 rules to langstroth app.
Review response. Removed test/settings.py
Removed accidental nodeenv dependency for tox.ini
Removed logging.
Removed monthly binning.
Changed implementation of user statistics so its no longer a class.
Generalised implementation of graphite response filtering and moved it to langstroth app.

Change-Id: I3b7dfd87310582fb1fab491ad37d82f9417efca5