update pypl description and add classifiers (#24)

Author: jbonzo

README.md

@@ -2,6 +2,8 @@
 
 # Polygon Python Client - WebSocket & RESTful APIs
 
+Python client for the [Polygon.io API](polygon.io)
+
 ## Getting Started
 
 For a basic product overview, check out our [setup and use documentation](https://polygon.io/sockets)

setup.py

@@ -29,6 +29,7 @@ def get_readme_md_contents():
         "License :: OSI Approved :: MIT License",
         "Programming Language :: Python :: 3",
         "Operating System :: OS Independent",
+        "Topic :: Office/Business :: Financial :: Investment"
     ],
     install_requires=[
         "websocket-client==0.56.0",