Fix the licensing issue mentioned in #2.

This commit:
- Relicenses MalbolgeLisp to GPLv3.
- Separates Matthias' init_module code and the lisp interpreter code.
- Updates the build instructions

Because the init_module code is licensed under GPLv3, by the virtue of using it as an interpreter, MalbolgeLisp may also need to be licensed under GNU GPLv3.

The source code to init_module code covered by GPLv3 has not been disclosed, only the Malbolge code has been made available, hence, it is sufficient to relicense the Malbolge code to MalbolgeLisp.

The commit also removes the historical versions of MalbolgeLisp

README.md

@@ -1,6 +1,6 @@
 
 # MalbolgeLISP v1.2
-Made by Palaiologos, 2020 - 2021. Released to the public domain.
+Made by Palaiologos, 2020 - 2021. Released under the terms of the GNU GPLv3 license.
 
 ![Session gif](https://github.com/kspalaiologos/malbolge-lisp/raw/master/session.gif)
 
@@ -72,4 +72,11 @@ A cat program that doesn't terminate on EOF:
 
 ## How to use
 
-Download and compile `fast20.c` using `clang` with `-O3 -march=native`. Unpack `lisp.zip` and run `./fast20 lisp.mb`.
+```
+$ git clone https://github.com/kspalaiologos/malbolge-lisp
+$ cd malbolge-lisp
+$ unzip lisp.mb
+$ clang -O3 -march=native fast20.c -o fast20
+$ cat init_module.mb core.mb > lisp.mb
+$ ./fast20 lisp.mb
+```