Removed old code.
Fixed assignment compilation.
Turned the Program struct into a class.
Updated VM to use the compiled code.

This is not completely done yet.
Added EndType instruction.

This instruction is appended to the program to signal that execution
should end.
Fixed FalseJump and TrueJump instructions.

FalseJump and TrueJump should not remove the top value from the stack.
Added And, Or, and End instructions to VM.
Added Hello World test.
Cleaning up.
Updated tests.
Added print method to Program class.

Useful to debug the generated bytecode.
Fixed binary operations bug.
Cleaning up.