[services-ng]Support postgresql 9.2

1. Add two blobs: postgresql9.2 and initdb9.2 (the OSS package is built using https://github.com/mflu/build_portable_postgresql )
2. Add postgresql92 package
3. Add postgresql.conf.erb in postgresql_node_ng job

Change-Id: Iaf2d985862f4097f9202a548560adf6381a37153