Added transaction projection for transactions - additional channel property

This PR relates to issue: https://github.com/jembi/openhim-core-js/issues/208. It also incorporates issue: https://github.com/jembi/openhim-console/issues/132 as well as issue: https://github.com/jembi/openhim-core-js/issues/190
It's good practice to always add a default case (just `else`). Maybe the best would be to make `simple` the default case.