make our docs job nitpicky and fix every broken link
diff --git a/docs/conf.py b/docs/conf.py
index f674ebe..5a4c41b 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -58,6 +58,8 @@
# Add any paths that contain templates here, relative to this directory.
templates_path = ['_templates']
+nitpicky = True
+
# The suffix of source filenames.
source_suffix = '.rst'
@@ -268,6 +270,6 @@
# texinfo_show_urls = 'footnote'
# Example configuration for intersphinx: refer to the Python standard library.
-intersphinx_mapping = {'https://docs.python.org/': None}
+intersphinx_mapping = {'https://docs.python.org/3': None}
epub_theme = 'epub'