Suggestion: optional use of css-html-js-minify

Hi! In order to reduce the render files as well as _repr_html, why not use css-html-js-minify: Example:

def _repr_html_(self):
        self.chart_id = uuid.uuid4().hex
        html = super()._repr_html_()
        try:
            from css_html_js_minify import html_minify
            html = html_minify(html, comments=False)
        except ImportError:
            pass
        return html

[ffarella]

This minifies also JS!!! (i.e chart options). I reduced my export size by about 5 (huge numpy array for time-series) by using this. Converting pandas Series and numpy arrays to list adds a lot of whitespace…

[ffarella]

No need for minification! Just change the dump parameter to: json.dumps(options, indent=None, cls=TRANSLATOR.json_encoder, separators=(',', ':'))