DOC: add python 3.8 support to setup.py spec.

Author: pavlov99

setup.py

@@ -43,6 +43,7 @@ def read(fname):
         "Programming Language :: Python :: 3.5",
         "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
+        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: Implementation :: PyPy",
         "Topic :: Software Development :: Libraries :: Python Modules",
     ],