Limit print_code to printing assembled code

Instead of the entire array, whether or not it was used in its entirety.
Add support for five command-line options

The options:
	-p	Assembles a file and prints the resulting byte-code to stdout.
		Takes one arguments, which is the file to assemble.

	-e	Executes a file as if it were bytecode. Requires one argument,
		the name of the file to execute.

	-i	Interprets a file. Requires one argument, the name of the file
		containing the MARIE assembly code.

	-b	Assembles a file and writes the byte code to disk. Takes two
		arguments: the first is the name of the file containing the
		source code. The second is the name of the file where the
		byte code will written.

	-h	Prints a usage message.