Re-do HalfAdder.hdl and FullAdder.hdl

Add project 2 skeleton files

Re-do And16.hdl, Not16.hdl, Or16.hdl, Or8Way.hdl

Re-do DMux4Way.hdl and DMux8Way.hdl

Re-do Mux4Way16.hdl and Mux8Way16.hdl

Re-do Mux.hdl, DMux.hdl, and Mux16.hdl

Re-do And.hdl, Not,hdl, Or.hdl, and Xor.hdl

Add README.md and PROGRESS.md

Initial commit, add project skeleton files