Recommend workout flow

<ul>
<li>WorkoutHistoryActivity -> SportActivity when you click "Recommend Workout"
<li>SportActivity displays a list of workouts. 
<li>SportActivity -> ScheduleWorkoutActivity when you click a workout in SportActivity.
<li>ScheduleWorkoutActivity displays the workout name and a date/time picker.
<li>ScheduleWorkoutActivity -> TraineeListActivity when you click "Schedule Workout"
<li>In button click listener, API POST request sent to add workout to trainee's schedule.
</ul>