Implemented an equals() method override in order for the ArrayList.contains() function to work. This helps to check whether there are duplicates of certain objects.

Not all member variables are compared. Only important identifying member variables are checked (price, averageRanking, numberSold, etc. are not checked)
Implemented a getMedia() method to find a specific media object in the MediaStore lists and return an updated copy of the object to the caller.
Merge branch 'master' of https://github.com/EchoSource/cmpsc221-final.git
Cleaned up code.
Added getTotalSold() function to Media Store and cleaned up code.
numberParticularMediaSold and checkTotalSales should work now.
These two lines should work now.