Override Tailwind platform target with the :tailwind config

[JosephShering]

This change gives developers the ability to override the platform target of tailwind CLI. Developers can add a :target key on the config to override manually

This is to address issue #39.

After doing some digging and just testing the tailwind command line, the M1 release target is broken. After testing the regular mac osx distribution, it works just fine on my M1 Silicon. Therefore the logical option is to let developer override the tailwind target in the config.