Create a class named Song that models a song.  The class
should have private instance variables for a song's
	- title (String)
	- artist (String)
	- duration (int - number of second)
	- genre (String) (Pop, Rock, Alt, HipHop)

The class should have a constructor that takes 4 arguments
and initializes all 4 fields.

The class should have access methods (getters) but no modifer 
methods (setters).

The method should override the Object class' to string method.

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Write a csv text file named songs.txt that contains at least information
about at least 10 songs.

The data for each song should be on a separate line with commas between.

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Write a program named MusicCatalog that satisfies the following requirements:

- The program should ask the user for a filename, and then read the songs in the file into an array of Songs.

- The program should then repeatedly display the following menu and ask the user for a menu option and then perform the menu operation.

	1) Display all songs
	2) Display all songs with a given Title
	3) Display all songs by a given Artist
	4) Exit