add pid directory deletion in murano setup script

Currently when murano is uninstalled from system, the pid directory is not
removed, and it causes problems with reinstalling, because the owner of the
pid directory is no more exists in system due to deletion while uninstalling.
This fact prevents murano-api and engine from starting.

Change-Id: I88aac5e61445538807acc92b31c56ee1fcb023d6

setup.sh

@@ -283,6 +283,7 @@ function purge_init()
         esac
         rm -f "/etc/init.d/$_initscript" || retval=$?
     done
+    rm -rf "/var/run/murano" || retval=$?
     return $retval
 }
 function run_pip_uninstall()