Version 0.1
 - Basic support for all logging methods, prefixing all output with
   the canonical name of the log level other than 'info', and writing
   each line with a comment prefix.
 - Warning and higher go to STDERR like Test::More::diag, and Notice
   and below go to STDOUT like Test::More::note
 - Default filter is debug and below.
 - Support for custom dumpers, used for non-scalars passed to 'debug'
   or 'trace' or any of the formatting '*f()' functions.
