added support to allow user to specify an output file name.  if no name is specified, then use default (i.e. ./output/Ticket.csv)
adding tag column to ticket table
- added organization model
- added misc columns to users (tags, organizations, notes, etc)
- added support for exporting comments and users
- fixed up formatter::quote to return empty string upon nil
- minor fix in exporter.rb to add 's' to default output file
removed s from type
added group and organization export ability