Also remove package and module names from classes and functions.
Also remove stix2.base from docs. We hide all private classes and
functions from the docs, so the only thing the documentation for base
included was STIXJSONEncoder.
Note: The first cell in each .ipynb file contains code to suppress
tracebacks in output cells. Thus cells that generate exceptions will
only output the error, without the traceback, which makes the
documentation easier to read.
Chris Lenk