Remove requirements, specify flask versions in matrix.

Author: jwg4

.travis.yml

@@ -3,7 +3,12 @@ python:
   - "2.7"
   - "3.3"
   - "3.4"
+  - "3.5"
+env:
+  - FLASK=0.12
+  - FLASK=1.0
 install: 
-  - pip install -r requirements.txt
+  - pip install Flask==${FLASK}
 script: 
   - python -m unittest discover
+