Add a way to delete exercises

[BrandonVanderMey]

1. Click on Fit Tracker.
2. Click "+Exercise" a bunch of times. There's no way of removing extra exercises.

Fix: We need to put either a - Delete Exercise (button) Or put a button directly with the cell

Either way will work. It might be easier with a delete exercise button and a button to select from the list

[KyletheWolff]

Approved to work on.