Improve tox.ini, install py26 for travis.

Signed-off-by: Dan O'Reilly <oreilldf@gmail.com>
diff --git a/travis.sh b/travis.sh
index b53b960..e76d83b 100755
--- a/travis.sh
+++ b/travis.sh
@@ -111,21 +111,30 @@
   build_javanano
 }
 
+internal_install_python_deps() {
+  sudo pip install tox
+  sudo apt-get install -y python-software-properties # for apt-add-repository
+  sudo apt-add-repository -y ppa:fkrull/deadsnakes
+  sudo apt-get update -qq
+  sudo apt-get install -y python2.6 python2.6-dev
+}
+
+
 build_python() {
   internal_build_cpp
-  sudo pip install tox
+  internal_install_python_deps
   cd python
-  tox
+  tox -e py26-python,py27-python
   cd ..
 }
 
 build_python_cpp() {
   internal_build_cpp
-  sudo pip install tox
-  export   LD_LIBRARY_PATH=../src/.libs # for Linux
+  internal_install_python_deps
+  export LD_LIBRARY_PATH=../src/.libs # for Linux
   export DYLD_LIBRARY_PATH=../src/.libs # for OS X
   cd python
-  tox -- --cpp_implementation
+  tox -e py26-cpp,py27-cpp
   cd ..
 }