cmake transition cleanups

[jbush001]

The following projects still have manually generated Makefiles (which no longer work):

• tests/float
• tests/kernel/multiprocess
• tests/kernel/threads
• tests/kernel/vga

tests/render still use Makefiles and need to be converted (potentially to use runtest.py scripts)

There is still a makefile for tools/visualizer (which is Java based)

[jbush001]

All makefiles are now gone.