Output task options in verbose mode

Contrib tasks currently include `grunt.verbose.writeflags(options, 'Options');`. Now that we have standardized `this.options()` it would be nice if grunt could print out the options automagically in verbose mode.

![Screen Shot 2013-04-03 at 00 17 17](https://f.cloud.github.com/assets/170270/335739/2c1b067e-9c95-11e2-8192-6a9318ce3759.png)