Allow multiple parents and/or contact information per account

[karbassi]

Is your feature request related to a problem? Please describe.
Currently only one parent, email, and phone number is assigned to each account. Students may have multiple parents. Parents may have multiple phone numbers and email addresses.

Describe the solution you'd like

• Allow parents to add additional parents.
• Allow parents to add additional phone numbers.
• Allow parents to add additional email addresses.
• Allow parents to mark which email/phone is primary.