#3 rationalize quiet and verbose options

[David Cok]

There are various quiet and verbose command-line options
for mjc and mjdoc. These could stand some refactoring
and assessment of what is actually useful from a user's
perspective. The sense of the option is not always
intuitive - e.g. using -quiet makes mjc less quiet

mjc:
--quiet : some timing information but without file names
--verbose: lots of processing task information and some
file name information

mjdoc/doclet api:
-verbose: ignored, causes warning
-quiet: no doclet information