remove python 3.3 from CI, flake8 doesn't support it anymore

pietroalbini · pietroalbini · commit 147827a99c48 · 2018-12-22T21:41:13.000+01:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,7 +1,6 @@
 sudo: false
 language: python
 python:
-  - 3.3
   - 3.4
   - 3.5
 install:
