Adds py.typed for typing support according to pep 561 (electronstudio#135)

Author: TrapsterDK

pyray/py.typed

@@ -38,6 +38,7 @@ def has_ext_modules(foo):
         "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.7",
     ],
+    package_data={"raylib": ["py.typed"], "pyray": ["py.typed"]},
     packages=["raylib", "pyray"],
     include_package_data=True,
     setup_requires=["cffi>=1.17.1"],