title: travis " Segmentation fault " but works fine locally
body: <p>there, I ran into a 'Segmentation fault' error when using travis-ci for my project : <a href="https://github.com/litaotao/IPython-Dashboard/tree/v-0.1.5-sql-server-log" rel="noreferrer">IPython-Dashboard</a></p>
  
  <p>there is no error msg and it works fine on local, I feel a little confusing. any one can give any idea on fixing this, thanks.</p>
  
  <hr>
  
  <p>here is the travis build log on cloud:</p>
  
  <p><a href="https://travis-ci.org/litaotao/IPython-Dashboard/builds/99570869" rel="noreferrer">travis-log</a></p>
  
  <pre><code>$ nosetests --with-coverage --cover-package=dashboard
  
  ../home/travis/build.sh: line 45:  3187 Segmentation fault      (core dumped) 
  nosetests --with-coverage --cover-package=dashboard
  
  The command "nosetests --with-coverage --cover-package=dashboard" exited with 139.
  </code></pre>
  
  <hr>
  
  <p>here is the build log on local [osx]</p>
  
  <pre><code>taotao@mac007:~/Desktop/github/IPython-Dashboard$sudo nosetests --with-coverage --cover-package=dashboard
  .../Users/chenshan/Desktop/github/IPython-Dashboard/dashboard/tests/testCreateData.py:78: Warning: Can't create database 'IPD_data'; database exists
    conn.cursor().execute('CREATE DATABASE IF NOT EXISTS {};'.format(config.sql_db))
  /Library/Python/2.7/site-packages/pandas/io/sql.py:599: FutureWarning: The 'mysql' flavor with DBAPI connection is deprecated and will be removed in future versions. MySQL will be further supported with SQLAlchemy engines.
    warnings.warn(_MYSQL_WARNING, FutureWarning)
  ...
  Name                                    Stmts   Miss  Cover   Missing
  ---------------------------------------------------------------------
  dashboard.py                               13      0   100%
  dashboard/client.py                         1      0   100%
  dashboard/client/sender.py                 11      3    73%   26-27, 33
  dashboard/conf.py                           0      0   100%
  dashboard/conf/config.py                   29      0   100%
  dashboard/server.py                         0      0   100%
  dashboard/server/resources.py               0      0   100%
  dashboard/server/resources/dash.py         35     10    71%   36, 55-56, 67-69, 86-89
  dashboard/server/resources/home.py         40     12    70%   25, 28-30, 83-91
  dashboard/server/resources/sql.py          27     11    59%   30, 52-75
  dashboard/server/resources/status.py        8      1    88%   19
  dashboard/server/resources/storage.py      13      5    62%   26-28, 43-47
  dashboard/server/utils.py                  79     18    77%   20-24, 78-80, 82-83, 86, 96, 99-100, 126-127, 140-142
  dashboard/server/views.py                  21      1    95%   16
  ---------------------------------------------------------------------
  TOTAL                                     277     61    78%
  ----------------------------------------------------------------------
  Ran 6 tests in 4.600s
  
  OK
  taotao@mac007:~/Desktop/github/IPython-Dashboard$
  </code></pre>