Bump deps for security

requirements.txt

@@ -22,9 +22,9 @@ psycopg2==2.7.3
 py-bcrypt==0.4
 python-dateutil==2.5.3
 python-postmark==0.4.10
-requests==2.20.*
+requests==2.22.0
 six==1.9.0
 smartypants==1.8.6
 stripe==2.29
-urllib3==1.24.2
+urllib3==1.25.3
 whitenoise==3.2.2