Removed criticalcss
Removed 'loud' comments
Environment task now changes Sass output style

Removed cssmin:deploy task, since it's no longer needed; set cssmin:critical to run pre-build; removed site.css_ext and all references in _includes/head.html
Removed grunt all
Include _includes/critical.min.css so it's available without `grunt cssmin`
Updated package versions
Updated environment task
Removed grunt-banner
Removed robots.txt since it was empty
Removed time-grunt