Finally have things printing to the screen

Nothing fancy yet. This commit adds a bunch of stuff (oops):

* compiling code
* VM with instructions
* remove eval.rs and just eval in the Machine struct itself
* squash most warnings now that we're using stuff here

And probably more. But that's all for now folks

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

src/vm/mod.rs

@@ -1,3 +1,3 @@
 pub mod error;
-pub mod eval;
+pub mod inst;
 pub mod machine;