update license classifier to a valid MIT License

Author: junioreif

setup.py

@@ -18,7 +18,7 @@
     author=["Antonio Bento de Oliveira Junior","Vinicius de Godoi Contessoto"],
     author_email="[email protected],[email protected]",
     classifiers=[
-        "License :: MIT",
+        "License :: OSI Approved :: MIT License",
         "Operating System :: OS Independent",
         "Programming Language :: Python :: 3",
         "Topic :: Software Development :: Libraries :: Python Modules",