Scheduled monthly dependency update for December (#316)

* Update pygments from 2.2.0 to 2.3.0

* Update sphinx from 1.8.1 to 1.8.2

* Update coverage from 4.5.1 to 4.5.2

* Update pytest from 3.9.3 to 4.0.1

* Update pytest-sugar from 0.9.1 to 0.9.2

docs/requirements.txt

@@ -1,4 +1,4 @@
 docutils==0.14
-Pygments==2.2.0
-Sphinx==1.8.1
+Pygments==2.3.0
+Sphinx==1.8.2
 sphinxcontrib-websupport==1.1.0

tests/requirements.txt

@@ -1,13 +1,13 @@
 attrs==18.2.0
 black==18.9b0
-coverage==4.5.1
+coverage==4.5.2
 flake8==3.6.0
 isort==4.3.4
 mypy==0.641
 pycodestyle==2.4.0
 pyflakes==2.0.0
-pytest==3.9.3
+pytest==4.0.1
 pytest-cov==2.6.0
 pytest-isort==0.2.1
 pytest-mock==1.10.0
-pytest-sugar==0.9.1
+pytest-sugar==0.9.2