Follow up fix for Bug 970150

It turns out that 6400c02 wasn't really working.
The inner `if` clause, `$?` is `0` no matter what the result from
the app name check, so that any app name would fail for Rails.

This fixes that.

cartridges/openshift-origin-cartridge-ruby/bin/control

@@ -191,8 +191,7 @@ function rails_app_name_check() {
   if [ -f Gemfile.lock ]; then
     grep 'rails' Gemfile.lock 2>&1 >/dev/null
     if [ $? -eq 0 ]; then
-      echo "$OPENSHIFT_APP_NAME" | grep '^[0-9]' >/dev/null
-      if [ $? -eq 0 ]; then
+      if $(echo "$OPENSHIFT_APP_NAME" | grep '^[0-9]' >/dev/null); then
         client_error "Invalid Rails application name. Please delete this application and re-create it with a name which does not start with numbers"
         exit 1
       fi