DOC: closes gh6838. Breakout options.rst from basics.rst

closes #6838. 
closes #3104 
Breakout "options" section for docs, heavily using info already in ``basics.rst``. Expands examples, and turns ``describe_options`` into a table.
The content is in there, with examples given for ``large_repr`` , ``expand_repr``, and ``max_rows``.  The other items are much more clearly described in the table at the bottom. I'm happy to put the FAQ question back in, however, with this iteration of the docs, it should be much easier to find.