Merge pull request #10 from b3/hotfixes

Allow format variable to be defined in main configuration file.
  Added HTML formatter for completeness.

  Now that we have a global "format = " configuration value
 we should have a default formatter that renders HTML (i.e. unchanged).

  This allows things to continue working as I expect and removes
 the special case of HTML == NOP.  Now you choose a formatter, always,
 just the default is HTML.