Create physical parameter example notebook

[raphaelshirley]

Feature request
@olivierilbert wants to have a notebook demonstrating the computation of physical parameters with ZFIX

• I have described the purpose of the suggested change, specifying what I need the enhancement to accomplish, i.e. what problem it solves.
• I have included any relevant links, screenshots, environment information, and data relevant to implementing the requested feature, as well as pseudocode for how I want to access the new functionality.
• If I have ideas for how the new feature could be implemented, I have provided explanations and/or pseudocode and/or task lists for the steps.

[raphaelshirley]

Essentially run the COSMOS example with the specz objects and BC03 templates and zfix for a 1000 objects and investigate the stellar masses?