Add support for standalone exe, GUI

Create setup.py using cx_freeze to allow for the flush_matrix script to be
run as a standalone exe file (no need for python installation on the
computer running the file). Add a mockup ui file (built using qt)
to outline the look-and-feel of the flush_matrix GUI for when the program
is refactored down the road.
Add ui files and executables.
Delete duplicated files

Remove the extra 'build' folder within src; we only want the build folder
in the project root.