[travis] Add missing dependencies

.travis.yml

-matrix: 
-  allow_failures: 
+
+matrix:
+  allow_failures:
   - compiler: clang
 script: ./.travis/build
 language: cpp
-after_success: 
+after_success:
 - coveralls -e _travis/install -e tests
 - git config --global user.name "Travis CI"
 - git config --global user.email "thomas.moulard+travis@gmail.com"
 - git remote set-url origin https://thomas-moulard:${GH_TOKEN}@github.com/stack-of-tasks/dynamic-graph.git
 - git fetch origin gh-pages:gh-pages
 - cd _travis/build/doc && ../../../cmake/github/update-doxygen-doc.sh
-branches: 
-  only: 
+branches:
+  only:
   - master
-notifications: 
-  email: 
+notifications:
+  email:
   - hpp-source@laas.fr
-before_install: 
+before_install:
 - git submodule update --init --recursive
 - sudo apt-get update -qq
-- sudo apt-get install -qq doxygen doxygen-latex libboost-all-dev libeigen3-dev liblapack-dev libblas-dev gfortran
+- sudo apt-get install -qq doxygen doxygen-latex libboost-all-dev libeigen3-dev liblapack-dev libblas-dev gfortran python-dev
 - sudo pip install cpp-coveralls --use-mirrors
-env: 
-  global: 
+env:
+  global:
     secure: kxgFbSRYzVa2zL4u3V+53D/cte66pnqWriB/em9Jslaa7EGu9xEV57nXzsSRJe29xdSipAY56RgehjoMo36DtpTO/5zj2aeIscYQac47fTvZmgI0UazyMnhDR1uB8UIy01U4NdXyGgLKNW1kWA48ulw+e7+FpOpnlAztyNZBIwk=
-compiler: 
+compiler:
 - clang
 - gcc

.travis/build

@@ -35,6 +35,7 @@ install_dependency()
 install_dependency jrl-umi3218/jrl-mathtools
 install_dependency jrl-umi3218/jrl-mal
 install_dependency stack-of-tasks/dynamic-graph
+install_dependency stack-of-tasks/dynamic-graph-python
 install_dependency stack-of-tasks/sot-core
 install_dependency stack-of-tasks/soth