make phone number in register have more validators

[epicasino]

• [x] validate if phone number is in use
• [x] throw error if phone number is in use
• [x] format phone number after it being valid

issue: if phone is invalid, and somehow user goes through login, user account is created with no phone number attached

[epicasino]

[front-end 59b741c] phone number in register now has more validators