** Implement to create your own Fancordion commands. ** To use your own command in a specification, add it to the 'FancordionRunner':** ** runner := FancordionRunner()** myCmd := MyCommand()** runner.commands["mycmd"] = myCmd** mixin Command {** If 'true' then this command can be ignored should a previous command fail.** ** Defaults to 'true'.virtual Bool canFailFast(){true}** Runs the command with the given URI and text. abstract Void runCommand(FixtureCtx fixCtx, CommandCtx cmdCtx)}