Updated data to match new format

- Updated data.json to match the new format for the demo
Bug Fixes

- Fixed some typos
- Fixed some things that referenced previous data structure
Fixed style

- Fixed style issues to try and make everything use classes
refreshContacts is working now

- If refreshContacts is called, it will load the appropriate contacts.
If null is passed, it generates the html for all contacts, whilst if
you pass a string value, it will return only contacts in that group.
- No validations done yet to make sure the string value exists, or if
cases are mismatched.
Set style for contacts list

— Checkpoint for now
- Made some style changes to the contacts list