Updated README.md file
Updated README.md file

Fix to httpd-vhost.conf file name.
devdrops/cha-sort,devdrops/openshift-silex-application,devdrops/silex-application,Diego-Brocanelli/openshift-silex-application,DevGears/cha-sort,devdrops/cha-sort,DevGears/cha-sort,devdrops/openshift-silex-application