Replace before_script for before_install

.travis.yml

@@ -1,6 +1,8 @@
 # http://travis-ci.org/#!/MongoEngine/mongoengine
 language: python
 services: mongodb
+before_install:
+    - "mongo --eval 'db.runCommand({setParameter: 1, textSearchEnabled: true})' admin"
 python:
     - "2.6"
     - "2.7"
@@ -33,8 +35,6 @@ install:
     - pip install https://pypi.python.org/packages/source/p/python-dateutil/python-dateutil-2.1.tar.gz#md5=1534bb15cf311f07afaa3aacba1c028b
     - python setup.py install
 
-before_script: mongo --eval 'db.adminCommand( { setParameter : 1, textSearchEnabled : true } )'
-
 script:
     - python setup.py test
     - if [[ $TRAVIS_PYTHON_VERSION == '3.'* ]]; then 2to3 . -w; fi;