Bypass an error only happen on Travis CI's Py3.5

Author: rayluo

setup.py

@@ -8,12 +8,17 @@
     io.open('msal_extensions/__init__.py', encoding='utf_8_sig').read()
     ).group(1)
 
+try:
+    long_description = open('README.md').read()
+except OSError:
+    long_description = "README.md is not accessible on TRAVIS CI's Python 3.5"
+
 setup(
     name='msal-extensions',
     version=__version__,
     packages=find_packages(),
-    long_description=open('README.md').read(),
-    long_description_content_type="text/markdown",    
+    long_description=long_description,
+    long_description_content_type="text/markdown",
     classifiers=[
         'Development Status :: 2 - Pre-Alpha',
     ],