Add a G-Machine interpreter for debugging

[Ailrun]

Is your feature request related to a problem? Please describe.
It is really hard to debug G-Machine transpiler with the current setting.

Describe the solution you'd like
Implement a G-Machine interpreter.

Additional context
See https://github.com/Ailrun/core-lang-haskell for a reference.

[Ailrun]

Dev note
Use Maybe Instruction as a return type of the monad.

[Ailrun]

Dev note
Add InterpreterStepMonad
(For undo function)

[Ailrun]

Dev note
Possible commands for CUI

• help
• run
• step
• undo (I believe that last two command should have the names related with each other in some manner. It's not the case for the listed names, so I wonder what are better name for them.)
• break (both adding and removing break commands are included)
• show (a command to display current state)
• etc.

[Ailrun]

Dev note
Current GMachineMonadT is completely broken. Or rather, interpretProgram is broken.
It's impossible to implement checkInterpreterFinished.

[Ailrun]

Dev note
Rename checkInterpreterFinished and others to use GMachine instead of Interpreter.

[Ailrun]

Dev note
Specification for Unwind instruction is broken. Fix it.
(Especially for CAF)

[Ailrun]

Dev note
If possible, make the interpreter lazy so that it can print intermediate results before a program finishes.
(Be careful with the implementability of undo command. It might not able to implement if the interpreter becomes lazy)
I think by using two or more data structure simultaneously, it is possible to implement the interpreter in a lazy and undo-able way.
The previous solution is not possible. Think the next example.

lazyEvalResult = st0 : st1 : ...
undoResult = st0 : ...
modifyResult = st0 : st1' : ...
{- but st1 is already considered as a part of the result in 'lazyEvalResult' -}

Maybe it is possible by changing state structure entirely, like the next description.

lazyEvalResult = State st0 : State st1 : ...
undoResult = State st0 : State st1 : Undo : ...
modifyResult = State st0 : State st1 : Undo : State s1' : ...

I'm not totally sure this works well or not though.