BLD: add locale to 34_nslow build

Author: jreback

.travis.yml

@@ -229,6 +229,7 @@ matrix:
         env:
           - PYTHON_VERSION=3.4
           - JOB_NAME: "34_nslow"
+          - LOCALE_OVERRIDE="zh_CN.UTF-8"
           - NOSE_ARGS="not slow and not disabled"
           - FULL_DEPS=true
           - CLIPBOARD=xsel