Improve fervor development tools

[parris]

Right now it can be pretty tricky to update fervor and test it locally. Doing simple things is not so hard. Things like, editing CLI tools or updating dependencies are pretty tricky. Even adding docs and chatting about it is not really enough. I think something needs to change.

Ok major problems:

• Adding dependencies requires a yarn add file:./../fervor/ followed by a yarn link
• Changing CLI tools requires uninstallation of fervor globally
• After playing with link enough your fervor instance will disappear and start getting babel errors