We need to improve the use of general prints to stderr/out.

Use a disciplined logging mechanism - presumably some standard scala logging mechanism with the usual controls over verbosity.

We need to standardize the format of the messages, and perhaps make use of indenting to make the traces easier to read.

Goal: a trace facility for compilation time, and for run-time, which is useful for showing what Daffodil is doing during each phase, and highlighting how decisions are being taken at compile time that therefore don't need to be tested or considered at runtime.

This is target s1 since improved logging/messages would be good to demo at CDTF, which is April 25.

We should also be able to shut off all logging overhead for performance testing, but that's a longer term need. Often the same controls for verbosity will also provide this, so that's why it is mentioned here.