Add related project URLs for display on PyPI

Adding `project_urls` and `keywords` to setup.py ensures they will be
available for the PyPI package page and any other place/service that
may look for these fields.

setup.py

@@ -33,11 +33,17 @@ setup(
     name='pelican',
     version=version,
     url='https://getpelican.com/',
-    author='Alexis Metaireau',
-    maintainer='Justin Mayer',
+    author='Justin Mayer',
     author_email='authors@getpelican.com',
     description="Static site generator supporting reStructuredText and "
                 "Markdown source content.",
+    project_urls={
+        'Documentation': 'https://docs.getpelican.com/',
+        'Funding': 'https://donate.getpelican.com/',
+        'Source': 'https://github.com/getpelican/pelican',
+        'Tracker': 'https://github.com/getpelican/pelican/issues',
+    },
+    keywords='static web site generator SSG reStructuredText Markdown',
     license='AGPLv3',
     long_description=description,
     packages=['pelican', 'pelican.tools'],