Include guide to use a virtual environment

[prateekj117]

It is always better to use a Virtual Environment when developing a Project. The README should include steps to set up the project locally using a Virtual Environment.

Can use PipEnv or virtualenv.

[mmlampinen]

For what's in the LED GitHub, most of these relate to use cases, prototypes and such, which are built on top of Prifina or open standards (for now, these are prototypes). This means there hasn't really been a need for environmental docs, but certainly its a good point for more specific projects and repos.