Warn about unsupported new pycparser version

Author: oprypin

generate/README.md

@@ -1,6 +1,6 @@
 Run *generate.sh* on Linux to (re)generate *lib* and *obj* source files based on CSFML's header files.
 
-This automatic generator expects the header files to be under *CSFML/include/SFML*. It requires [Python][] 3.3+ and [pycparser][].
+This automatic generator expects the header files to be under *CSFML/include/SFML*. It requires [Python][] 3.3+ and '[pycparser][]==**2.1.0**'.
 
 The generator's code is very messy, and there are some specific replacements that make the word "automatic" a bit dishonest. Still, it should allow transitioning to new CSFML versions with little to no intervention.