Add "Bug Tracker" and "Documentation" links to setup.py

They show up on the pypi page on the left, making
them easier to find.

Signed-off-by: Attila Szakacs <attila.szakacs@axoflow.com>

setup.py

@@ -199,6 +199,7 @@ def run(self):
     description=nacl.__summary__,
     long_description="\n".join((README, INSTALL, CHANGELOG)),
     url=nacl.__uri__,
+    project_urls=nacl.__project_urls__,
     license=nacl.__license__,
     author=nacl.__author__,
     author_email=nacl.__email__,

src/nacl/__init__.py

@@ -17,6 +17,7 @@
     "__title__",
     "__summary__",
     "__uri__",
+    "__project_urls",
     "__version__",
     "__author__",
     "__email__",
@@ -30,6 +31,11 @@
 )
 __uri__ = "https://github.com/pyca/pynacl/"
 
+__project_urls__ = {
+    "Bug Tracker": "https://github.com/pyca/pynacl/issues",
+    "Documentation": "https://pynacl.readthedocs.io/",
+}
+
 __version__ = "1.6.0.dev1"
 
 __author__ = "The PyNaCl developers"