Script for publishing persistent UDFs

[jklukas]

We should have a script to run through the udf/ directory and publish all of them as persistent UDFs in the udf dataset.

As part of this, we may want to alter the file names and definition files to not include a udf_ prefix, and only insert that prefix when we're generating files in sql/ to provide temporary view definitions.

Or, we can leave the files as is and have the script's logic strip the prefix when publishing to the udf dataset.

[jklukas]

We should also add documentation to docs.tmo about the published UDFs as part of this effort.