Update home page content

[theecrit]

Checklist

• [x] Add description
• [x] Reference the open issue that the pull request addresses
• [x] Pass code quality checks
  • spin up docker docker-compose up -d --build
  • enter api container docker-compose exec api /bin/bash
  • run api tests make validate
  • exit container ctrl/command+D or exit
  • enter web container docker-compose exec web /bin/sh
  • run front-end tests npm run test or npx jest
  • lint npm run lint-fix
  • exit container as above
• [x] Request code review
  • Please allow 36 hours from opening a pull request before merging a pull request- even if it has already received an approving review.
• [x] Address comments on code and resolve requested changes
• [ ] Merge own code

Description

Issue: #467

Brief description of solution

• Adds brief explanation of WOAQ and pushes visitor to map page
• Adds volunteer sign-up path (lean)
• Tweaks site fonts to conform to Semantic defaults

NOTE: I'm not sure how to run tests without Docker...