Speed up viz page load/ by streaming trend computation?

[brownsarahm]

it's getting really slow on initial load, maybe we could use one of these patterns to load result df and compute the bivariate matrices one trend at a time?

http://flask.pocoo.org/docs/1.0/patterns/streaming/

I can change get_subgroup_trends_1lev to append results instead of overwriting so that it the viz can do something like

trend_list = [corrobj,rankobj,linreg_obj]
for trend in trend_list:
    labeled_df.get_subgroup_trends_1lev(trend)