Chuck force clean dev

@etpinard @theengineear @chriddyp - These changes are to address the errors we are getting when someone attempts to view the code associated with a given plot (e.g: https://plot.ly/~wormie_dk/1.json) and the type associated with any of the traces is either invalid (e.g. type = lines) or deprecated (ex. type = histogramx). The errors are occurring on our backend because we're using the python wrapper to force clean the json before making the translation. The biggest change I’m making here is forcing invalid types to be “scatter” (that’s what we’re doing on the front end anyway) and throwing a warning to the user. Thoughts?