Exported variables go to the design specifications to be inserted into the rst

[fletchapin]

This has already been started. We just need to finalize how to add this function in to the Sphinx build logic. Right now our approach is to insert the function into setup() in conf.py

[fletchapin]

All variables are now exported into global.rst which is in turn included in each .rst file. The variable names from Onshape still do not match up with the .rst variable names, but that is covered in #6