Update requirements

Generated from pipenv with:

  $ pipenv lock -r > requirements.txt
  $ pipenv lock -r -d > requirements-dev.txt

requirements-dev.txt

@@ -1,5 +1,4 @@
 -i https://pypi.org/simple
-atomicwrites==1.3.0
 attrs==19.3.0
 backcall==0.1.0
 decorator==4.4.1
@@ -14,15 +13,15 @@ packaging==19.2
 parso==0.5.1
 pexpect==4.7.0 ; sys_platform != 'win32'
 pickleshare==0.7.5
-pluggy==0.13.0
+pluggy==0.13.1
 prompt-toolkit==2.0.10
 ptyprocess==0.6.0
 py==1.8.0
 pycodestyle==2.5.0
 pyflakes==2.1.1
-pygments==2.4.2
+pygments==2.5.1
 pyparsing==2.4.5
-pytest==5.2.3
+pytest==5.3.1
 six==1.13.0
 traitlets==4.3.3
 wcwidth==0.1.7

requirements.txt

@@ -2,7 +2,7 @@
 certifi==2019.9.11
 chardet==3.0.4
 falcon==2.0.0
-gunicorn==20.0.0
+gunicorn==20.0.4
 idna==2.8
 psycopg2-binary==2.8.4
 requests==2.22.0