Adding test for loading immediate 16 bits into SP.
Adding completed/passing test for push.
Adding flow chart of how 'push' works.
Added changes for how MDR works (microcode bits for load and width rather than load_h and load_h).
Added support for running tests on RAM contents.
Bug fixes for RAM writes (works now!) and added the type of RAM written to the "RAM write" debug output.
Finished 'push' instruction, fully working per unit test.