Dropped support for python 2.6 and added python 3.5

.travis.yml

 language: python
 matrix:
   include:
-  - python: 2.6
   - python: 2.7
     env:
     - secure: HYFSm84gCi+EnE3hDeRfPFojhfPx7RS7xfP2cYs+tzOvE2DdL62D4ZA/bnBTCbIl4FyOKxS/3biLYu40d8UIjDYvMgx8xaT/byJB6iw4my9vnzkFl2NcbBNQA0NvoU8lBrS/zXrbz3U/JMLNDXlGDFx/GTMmvAYt2Hrttq9kxD4=
@@ -10,6 +9,7 @@ matrix:
     - BOB_UPLOAD_WHEEL="--universal"
   - python: 3.3
   - python: 3.4
+  - python: 3.5
 before_install:
 - sudo add-apt-repository -y ppa:biometrics/bob
 - sudo apt-get update -qq