[doc] quick-start guide issues

[nongarak]

What happens?

1. To use the %sqlplot boxplot code suggested in the quick-start guide requires installation and importing of matplotlib, which the guide does not suggest. import matplotlib or import matplotlib.pyplot as plt should be added either before it's called or in the setup snippet at the top of the page.
2. To use the pandas integration one must also install pandas, which should be imported in the setup snippet as well. import pandas as pd should be added either before it's called or in the import snippet at the top of the page.

To Reproduce

Running the notebook without these import statements results in errors without matplotlib or pandas imported.

OS:

macOS

JupySQL Version:

0.11.1

Full Name:

Alex Nongard

Affiliation:

CFPB