Add ability to filter students on Instructor Dashboard

[tp02ga]

This will be the task to add the filtering in the back-end.
Return a sub-set of students based on data like:

• active / inactive
• graduated
• dropped
• behind
• ?
• ?
• ?

[Tymiceli]

Filter students based on:

• currentStatus
• sponsoredBy (app.prop env. variable (@ value))
• zoomHandle
• gmail
• githubHandle
• linkedinHandle

Create enum for user class:

public enum CurrentStatus {
ACTIVE,
INACTIVE,
PROBATION,
DROPPED,
PAUSED,
NOT_RESPONSIVE,
BEHIND3_PLUS,
BEHIND3,
GRADUATED;
}

• enable client side view mods for above inputs
• for this view https://assignments.coderscampus.com/instructors/dashboard:
  • filters out entirely CurrentStatus of inactive, dropped, paused, notResponsive unless specifically requested
  • displays CurrentStatus of probation in single column if not filtered out
  • option to filter out all but one of CurrentStatus (equivalent to "hey, just show me the active students")