docs: update url, add doc url to setup.cfg

Author: machow

setup.cfg

@@ -3,7 +3,9 @@ name = pins
 description = Publish data sets, models, and other python objects, making it easy to share them across projects and with your colleagues.
 long_description = file: README.md
 long_description_content_type = text/markdown
-url = https://github.com/machow/pins-python
+url = https://github.com/rstudio/pins-python
+project_urls =
+    Documentation = https://rstudio.github.io/pins-python
 author = Michael Chow
 author_email = [email protected]
 license = MIT