Fix travis.yml

Author: methane

.travis.yml

@@ -2,5 +2,7 @@ services:
     - memcached
 language: python
 python: 3.3
-before_script: "pip install tox"
+before_script:
+    - "pip install --upgrade pip"
+    - "pip install tox pymemcache flask"
 script: "tox"