build SymPy from source, then make modifications to ANTLR

The objective of this repo is to provide a set of working Latex examples that trigger parsing errors in Sympy.

All of the Latex is valid, as demonstrated that each tex file compiles to dvi, without error.

The goal is to modify the SymPy ANTLR grammar such that no errors occur.

Resources for Latex symbols:

• https://www.bu.edu/math/files/2013/08/LongTeX1.pdf