exploiting new travis-ci environment

.travis.yml

@@ -1,5 +1,11 @@
 language: python
 
+sudo: false
+
+cache:
+  directories:
+    - $HOME/.pip-cache/
+
 python:
   - '2.6'
   - '2.7'
@@ -9,10 +15,10 @@ install:
   - pip install -e .
 
 before_script:
-  - if [[ $TRAVIS_PYTHON_VERSION == '2.6' ]]; then pip install unittest2; fi
-  #Temporal solution to travis issue #155
-  - sudo chmod 777 /dev/shm
-  - sudo rm -rf /dev/shm && sudo ln -s /run/shm /dev/shm
+  - if [[ $TRAVIS_PYTHON_VERSION == '2.6' ]]; then pip install --download-cache $HOME/.pip-cache unittest2; fi
+  - if [[ $TRAVIS_PYTHON_VERSION == '2.7' ]]; then pip install --download-cache $HOME/.pip-cache coverage; fi;
+  - if [[ $TRAVIS_PYTHON_VERSION == '2.7' ]]; then pip install --download-cache $HOME/.pip-cache python-coveralls; fi
+
 
 script: export COVERAGE_PROCESS_START=gluon/tests/coverage.ini; ./web2py.py --run_system_tests --with_coverage