Make scope pip-installable

[bfhealy]

This PR makes Scope pip-installable (initial version 0.9.0), using poetry to build the package. Changes include:

• Move scope.py to the scope directory, rename to scope_class.py
• Instantiate a Scope object using scope/_instantiate.py
• Add methods that use argparse to handle input to Scope methods in scope.py
• Define scripts to install in pyproject.toml
• Add function to generate directories, copy config defaults if no config exists
• Refactor scripts to have a main function that can be installed, take --config-path argument
• Revisit scope_class.py code to allow --config-path to be specified