** 0.05 / 2016-07-08
   - Change behaviour of Selectable widget (Radiobutton, Checkbox and Option)
     to return the empty string (false) when not selected for the 'value'
     attribute

** 0.04 / 2016-07-04
   - Fix timing problem initializing Session's 'page' attribute
     (depends on 'page_class') by making it lazy

** 0.03 / 2016-07-03
   - Allow overriding the class of the object instantiated
     into the 'page' attribute

** 0.02 / 2016-06-22 (TRIAL)
   - Adjusted dependencies based on testing in clean VM

** 0.01 / 2016-06-22 (TRIAL)
  - Initial release to replace LedgerSMB's
    (https://github.com/ledgersmb/LedgerSMB) test code