update dependency versions

Author: sheppard

.travis.yml

@@ -4,12 +4,14 @@ python:
  - "3.4"
 env:
   matrix:
-    - DJANGO="django==1.6.10" REST="djangorestframework==2.4.4"
-    - DJANGO="django==1.6.10" REST="djangorestframework==3.1.0"
-    - DJANGO="django==1.7.6"  REST="djangorestframework==2.4.4"
-    - DJANGO="django==1.7.6"  REST="djangorestframework==3.1.0"
+    - DJANGO="django==1.6.11" REST="djangorestframework==2.4.4"
+    - DJANGO="django==1.6.11" REST="djangorestframework==3.1.1"
+    - DJANGO="django==1.7.7"  REST="djangorestframework==2.4.4"
+    - DJANGO="django==1.7.7"  REST="djangorestframework==3.1.1"
+    - DJANGO="django==1.8" REST="djangorestframework==2.4.4"
+    - DJANGO="django==1.8" REST="djangorestframework==3.1.1"
   global:
-    - PANDAS="pandas==0.15.2"
+    - PANDAS="pandas==0.16.0"
 install:
  - pip install $DJANGO
  - pip install $REST