[src][test] Adding in initialization of graph and accompanying test
[src][test] Adding in tests and implementation for empty graphs
[test] Adding in some tests for testing neighbors, adding in some setter methods to vectors, matricies, and graphs
[src][test] Simple implementation of get neighbors and accompanying tests
[src] Adding in some documentation to getting graph node neighbors
[src][test] Simple implementation of setting an edge and accompanying test
[test] Adding additional assertions to graph tests
[test] Adding in a test for removing a graph edge
[src] Oof, last little bits of graph implementaiton
[src] moving graph node impl back into graph.h
[doc] Updating documentation
[README] Adding in desried data structures to README list