Make Daffodil version used easily findable

[stevedlawrence]

When using saved parsers, you must use a saved parser built with the same version of Daffodil that is embedded in the nifi-daffodil nar. Unfortunately, there isn't an easy way to know which version of Daffodil is embedded. You either need to list the files in the nar and look for the daffodil jars (e.g. unzip -l nifi-daffodil-nar-*.nar | grep -o 'daffodil-lib_.*'), or look at the pom for the nifi-daffodil release and see what version of daffodil it depends on.

Instead, it would be useful if we could add text somewhere within NiFi Daffodil properties or documentation to make it easier to figure out which version of Daffodil is being used.