Update registry.xml to include an example
Resolves
<!--
Uncomment below parameters (ConfigRegRoot, GovRegRoot, LocalRegRoot) to configure registry root paths
Default : <EI_HOME>/wso2/micro-integrator/registry/{governance | config | local}
+ Example : <parameter name="GovRegRoot">file:///Users/JohnDoe/registry/governance</parameter>
-->
<!--
<parameter name="ConfigRegRoot">{Root directory path for configuration Registry}</parameter>
