11 Dec 2014 - v0.05
    * New feature: watch expressions - send notification when an expression
        changes
    * Fix a bug when get_var_at_level() is called with a package-global hash

16 Aug 2014 - v0.04
    * Normalize stack frame 'hasargs' between different Perl versions
    * Stack frame instances get unique serial numbers
    * Breakpoint/Action 'code' is now mutable

24 Jun 2014 - v0.03
    * get_var_at_level() works properly with vstrings
    * Typo fixes from David Steinbrunner <dsteinbrunner@pobox.com>

8 Mar 2014 - v0.02
    * Fixed a packaging error.  Functionally the same as v0.01

3 Mar 2014 - v0.01
    * First release