Bug in travis early exits

[lheagy]

The latest pypi release deployed earlier than anticipated (thanks @jcapriot for catching this). It wasn't a problem as the deployed version was what we intended to deploy - however, it should have been deployed only upon the merge to master or the tagged release...

after_success:

  - bash <(curl -s https://codecov.io/bash)

  # early exit if not on a deplotment branch
  - if ! [ "$TRAVIS_BRANCH" = "$MASTER_BRANCH" -o "$TRAVIS_TAG" = "true" ]; then
      echo "Not deploying (because this is not a deployment branch)" ;
      exit 0 ;
    fi
  - if [ "$TRAVIS_PULL_REQUEST" = "true" ]; then
      echo "Not deploying (because this is a pull request)" ;
      exit 0 ;
    fi