Update .travis.yml file

Author: desecho

.travis.yml

@@ -4,10 +4,14 @@ python:
   - "2.7"
   - "3.4"
   - "3.5"
+  - "3.6"
 
 env:
   - DJANGO="Django>=1.9.0,<1.10.0"
   - DJANGO="Django>=1.10.0,<1.11.0"
+  - DJANGO="Django>=1.11.0,<2.0.0"
+  - DJANGO="Django>=2.0,<2.1"
+
 install:
   - pip install -q $DJANGO
   - pip install -r requirements.txt