Created DayHasExercises Table.
changed HasRelationship Table to ExerciseHasHistory Table
Merge remote-tracking branch 'origin/master'

Conflicts:
	app/src/main/java/com/group1/workouttracker/MainActivity.java
	app/src/main/java/com/group1/workouttracker/MySQLiteHelper.java
Updated MySQLiteHelper:
1. Created Day_Has_Ex Table.
2. Various fixes to make table names and column names more standardized