0.1.6
  Changed to parameterized logging with jlogger 0.0.4 for faster non-logging

0.1.5
  Changed to use jlogger
    
0.1.4
  Add dependency on Trollop to Rakefile
  
0.1.3
  ...and fixed signature for getISBNs
  
0.1.2
  Added custom function getISBNS
  
0.1.1
  Minor fixes to documentation of options
  
0.1.0 
  Initial public release