Improve repo's compatibility with windows

[ryankortbeek]

Bug Description

The current env.sh and update.sh scripts are only compatible with unix-like operating systems. The signal python module that is used in several places in the repository is also not used in a manner that is compatible with windows (e.g., comm.py). This task entails resolving both these issues:

• Rewrite env.sh and update.sh scripts to be compatible with windows
  • Update documentation to reference the correct script based on the OS that a reader is using
• Fix or remove usage of the signal python module (details can be found here
  • Find an alternative module that provides the same functionality

[jmmabanta]

Since the introduction of docker-compose in #92, these compatibility issues should be fixed since everything is running under a linux docker container. Should still be verified with a fresh copy of this repo on Windows.