[WIP] Scaffolding of various features

[infomiho]

Working on:

• [x] Tailwind CSS scaffolding
• [x] Auth scaffolding
• [ ] Email sender scaffolding

Biggest issues atm:

• the DX is not where we want it to be
  • we are prompting the user to edit the Wasp file by hand instead of doing it automatically
  • the blocker for automatic editing is figuring out the best way to edit Wasp's AST and pretty print it