chore: update docs

docs/requirements.txt

@@ -1,19 +1,27 @@
 alabaster==0.7.12
-Babel==2.3.4
-certifi==2018.11.29
+Babel==2.7.0
+cakephp-theme==1.0.2
+certifi==2019.11.28
 chardet==3.0.4
-docutils==0.14
-idna==2.7
-imagesize==0.7.1
-Jinja2==2.10.1
-MarkupSafe==0.23
-Pygments==2.3.0
-pytz==2018.7
-requests==2.20.1
-six==1.11.0
-snowballstemmer==1.2.1
-Sphinx==1.5.1
-sphinx-rtd-theme==0.1.9
-sphinxcontrib-phpdomain==0.2.1
-urllib3==1.25.2
-cakephp-theme
+docutils==0.15.2
+idna==2.8
+imagesize==1.1.0
+Jinja2==2.10.3
+MarkupSafe==1.1.1
+packaging==19.2
+Pygments==2.5.2
+pyparsing==2.4.5
+pytz==2019.3
+requests==2.22.0
+six==1.13.0
+snowballstemmer==2.0.0
+Sphinx==2.2.1
+sphinx-rtd-theme==0.4.3
+sphinxcontrib-applehelp==1.0.1
+sphinxcontrib-devhelp==1.0.1
+sphinxcontrib-htmlhelp==1.0.2
+sphinxcontrib-jsmath==1.0.1
+sphinxcontrib-phpdomain==0.6.2
+sphinxcontrib-qthelp==1.0.2
+sphinxcontrib-serializinghtml==1.1.3
+urllib3==1.25.7