Hierarchy

[audrey01mit]

Proposition to answer issue #31

• Broke the hierarchy in devices.

• The same can be done later for other modules more easily because generate_api and plot_images are automatized (no dependence on modules names).

• Broke geometries in geometries (hyp tap etc...) and tests (alignment, resolution etc...), and design in design (classes) and cells (pre-built cells).

• Updated documentation accordingly (check qnngds documentation for user and for dev).

• Created a __default_param.py file to store the default values in functions over the entire module.

[reed-foster]

Okay I created separate issues and replied to all the comments I originally left referencing those issues so that way only a few things need to be addressed here before merging.