Provide an option to not log mappings files mismatches

[mjordan]

Currently, the CdmToMods and CsvToMods metadata manipulators log when the mappings file contains a row for a field that is not in the incoming metadata. This is sensible default behavior but gets annoying when you're tying to parse through the verbose errors written to mik.log. We should provide a config option to turn this off.

[MarcusBarnes]

@mjordan Maybe included as part of a more general --verbose option?

[mjordan]

That's a good idea. I think if we added an entry to the [CONFIG] settings section dynamically (i.e., if the --verbose option was passed on the mik command line), we could then access that option in any of our class files to write out log entries. If we wanted to support verbosity levels, we could pass in an integer. There may be other implementations but it would be nice to not have to write a lot of code to make that work. OTOH if Monolog offers a verbosity mechanism other than its log levels, we may want to use it.