Update python minimal version

to 3.5, we stop supporting 3.4

setup.py

@@ -55,7 +55,6 @@ setup(
         'Intended Audience :: Developers',
         'Intended Audience :: System Administrators',
         'Operating System :: OS Independent',
-        'Programming Language :: Python :: 3.4',
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
         'Topic :: System :: Networking',
@@ -67,7 +66,7 @@ setup(
     },
     data_files=get_data_files(),
     keywords='tor onion bandwidth measurements scanner relay circuit',
-    python_requires='>=3.4.5',
+    python_requires='>=3.5',
     entry_points={
         'console_scripts': [
             'sbws = sbws.sbws:main',