Make Load Examples Optional

[Cheetos]

Is your feature request related to a problem? Please describe.

In libpysal/__init__.py, you have the following import.

from . import examples

and inside the __init__.py of the examples package, it is loading the examples every time, which is time-consuming.

Describe the solution you'd like

I was wondering if loading the examples could be optional since it is time-consuming because always loads the examples from the internet.

Describe alternatives you've considered

We have considered creating a Fork and avoiding loading the examples every time, but it is not desirable.

Additional context
Add any other context or screenshots about the feature request here.

[sjsrey]

xref #522