Add exercise_mod and modified:boolean to ExerciseSession
Add detail and duration alongside exercise link in workout#show
Create a model helper function for adding an exercise to a workout - refactor workout controller
Add workout add exercise helper function to exercise controller when new exercise is created
Add new column exercise_mod to workout#show view with link to modified exercise and updated logic in controllers - create a mod_counts model helper for workout#sessions for each user
update workout index and removed detail validation from exercise
Update mod count to check that exercise session workout is the same as workout session workout