Add documentation for running within tox
Add documentation for running within tox

Initial patch provided by David Zuber (@storax)

Fixes #64

ionelmc/coveralls-python,jvarho/coveralls-python,lolletsoc/coveralls-python,Jwpe/coveralls-python,coagulant/coveralls-python,jessamynsmith/coveralls-python,coveralls-clients/coveralls-python