ENH: set render limits on Styler to automatically trim dataframes

[attack68]

• closes ENH: add dataframe render trimming in Styler to avoid browser crash #40712 also linking CLN/API: implemented to_html in terms of .style #11700
• tests added / passed

Adds an option: styler.max.elements with a default value of 2**18 = 262144.

>>> pd.options.styler.max.elements = 2**18
>>> df = pd.DataFrame(np.random.rand(10000,100))
>>> %timeit df.style.render()
4.11 s ± 30.3 ms per loop (mean ± std. dev. of 7 runs, 1 loop each)

Even though this is a 'large' dataframe it is reduced to the max elements and still renders in reasonable time (4s plus about 5s for a browser to render the date).

If the number of data elements exceeds the max then the right side, or bottom, or both of the DataFrame will be trimmed (starting with the largest axis and recursively reducing), leaving '...' filler indicators.

All reduction takes place before index or data looping so it avoids any crashes.

[jreback]

not but on yet another option as we already have display.max_columns but i suppose ok

[jreback]

styler.display.max_elements ? i think something like that is more instructive no?

[jreback]

or
styler.render.max_elements (as all things are display based)

[attack68]

agreed, even maybe styler.max_elements, but changed to yours

[jreback]

thanks @attack68