added classifiers to the setup.py

Author: tushdante

setup.py

@@ -25,4 +25,11 @@ def getRequires():
     description='SendGrid library for Python',
     long_description=open('./README.rst').read(),
     install_requires=getRequires(),
+    classifiers=[
+        'Programming Language :: Python :: 2.6',
+        'Programming Language :: Python :: 2.7',
+        'Programming Language :: Python :: 3.2',
+        'Programming Language :: Python :: 3.3',
+        'Programming Language :: Python :: 3.4'
+    ]
 )