Error Message on Modal when Respose is not Sucessful

[aayush6194]

when res.sucess === false, modal should pop up and display the res.message

[ZachPoole]

UserStartPage was already done.
ClassDashboard updated.
Waiting on AddStudent route before adding Error message.

[ZachPoole]

Do you want the alert() or embedded into the UserModal component? @aayush6194