Fix the travis config to properly change webinos_config.

The travis configuration is supposed to change the
port number of the PZH Provider to enable it to run as
a user.  However, the old SED script was flawed.  This
patch fixes the regular expression

Jira issue: WP-793
Merge pull request #492 from jplyle/fix-travis-build

Fix the travis config to properly change webinos_config.