Remove 'make install_required_operators' from docs
Removes 'make install_required_operators' step from installation docs. This is primarily a CI-specific step, and with !172 (merged) this step requires an environment variable to be configured that users would not need.
Rather than using this make target, end users will continue to use the documentation near the top of the page that outlines the dependencies and provides links to documentation on how to install them.
Closes #208 (closed)
Edited by Mitchell Nielsen