add python3.6 and python3.7 CI test

Author: yangjunren

.travis.yml

@@ -4,6 +4,8 @@ python:
 - "2.7"
 - "3.4"
 - "3.5"
+- "3.6"
+- "3.7"
 install:
 - pip install flake8
 - pip install pytest

setup.py

@@ -65,6 +65,8 @@ def find_version(*file_paths):
         'Programming Language :: Python :: 3.3',
         'Programming Language :: Python :: 3.4',
         'Programming Language :: Python :: 3.5',
+        'Programming Language :: Python :: 3.6',
+        'Programming Language :: Python :: 3.7',
         'Topic :: Internet :: WWW/HTTP :: Dynamic Content',
         'Topic :: Software Development :: Libraries :: Python Modules'
     ],