v1.1_CMake_additions_to_1.0_release

Summary

This builds off of the 1.0 release to switch compilation to be based off CMake, and uses that to add unittesting via Google Test
The unittest suite is enough to be demonstrative but is not comprehensive like production code would be. However it did help catch issues with boundary checking and invalid initial conditions in the library.

What's Changed

• Converted compilation to CMake @ChaseStewart
• Added CMake steps to pull in Google Test by @ChaseStewart
• Created libpathfinding/unittest folder and suites test_pathfinding_algorithm.cpp and test_pathfinding_inputs.cpp by @ChaseStewart
• Updated README.md with setup/install/run instructions for main and test_pathfinding applications by @ChaseStewart

Full Changelog: https://github.com/ChaseStewart/libPathfindingCpp/commits/v1.1_CMake