Made checks if previous data is same as present

This check prevents the user from choking up the webserver with old
data.
Changed setInterval to setTimeout

This small change is BIG. Why does setInterval > setTimeout?
 - setInterval is making calls between a certain amount of time.
 - while setTimeout executes that amount of time and that gets called
   again.
 - what if the user's ajax request failed, then we will be sending old
   stale data back to them.
 - setTimeout sets a limit to how long the code should execute, if it
   takes longer than that, it stops running and creates a new process.