chore(project): update documentation dependencies

Author: kylef

docs/Pipfile.lock

@@ -1,23 +1,23 @@
--i https://pypi.org/simple
 alabaster==0.7.12
-babel==2.6.0
-certifi==2019.3.9
+attrs==19.1.0
+Babel==2.7.0
+certifi==2019.6.16
 chardet==3.0.4
-docutils==0.14
+docutils==0.15.2
 idna==2.8
 imagesize==1.1.0
-jinja2==2.10.1
-markupsafe==1.1.1
-packaging==19.0
+Jinja2==2.10.1
+MarkupSafe==1.1.1
+packaging==19.1
 parsimonious==0.7.0
-pygments==2.3.1
-pyparsing==2.4.0
+Pygments==2.4.2
+pyparsing==2.4.2
 pytz==2019.1
-requests==2.21.0
+requests==2.22.0
 six==1.12.0
-snowballstemmer==1.2.1
+snowballstemmer==1.9.0
+Sphinx==1.8.5
 sphinx-js==2.7.1
 sphinx-rtd-theme==0.4.3
-sphinx==1.8.5
-sphinxcontrib-websupport==1.1.0
-urllib3==1.24.2
+sphinxcontrib-websupport==1.1.2
+urllib3==1.25.3