Adding automatic record ID retrieval and dynamic YAML use.
Adding config file verification
Improved error messages & quiet config option

 - Adds quiet config option that suppresses stdout messages when
   the public IP didn't change from what's already in the record.
 - Prints errors to stdout in addition to raising exceptions when
   an error occurs so logs can be of use when debugging failures
   that crop up after the script has been stuffed into cron and
   forgotten.
 - Updates README for quiet option
 - Whitespace nits
Merge branch 'sullivanmatt-master'