Update p5-App-Cmd from version 0.206 to version 0.300.

Upstream changes:
0.300    2009-09-28
          DEPRECATED -run OPTION TO APP CLASS IMPORT
          "use MyApp -run;" is deprecated; it will be removed after no less
          than a year

          this led to problems where normal exit-on-error messages confused
          users by complaining about failing to compile; magic to stop this is
          not worth the tiny savings

          COMMANDS SHOULD NOW HAVE ->execute RATHER THAN ->run
          this will not break you code... except:

          WILL BREAK YOUR CODE: App::Cmd::Simple programs must use ->execute
          rather than ->run

0.207    2009-09-27
          add option to allow any unambiguous command abbreviation
          (thanks, Jerome Quelin)

(seb)