//members
private Scanner console
privvate int date
constructor
PRECONDITION: 	none
INPUT:		none
PROCESS:	It asks the user for the starting date and sets the variable
		date to the given starting date.  If the date is not between
		1 and 30, it gives an error message and asks again. It keeps
		asking until a valid date is given.  It also creates the 
		Scanner class with the console window as the input.
OUTPUT:		none
POSTCONDITION:  date is initialized and Scanner is created

today
PRECONDITION:	none
INPUT:		none
PROCESS:	It outputs the current date.
OUTPUT:		none
POSTCONDITION:	none

previous
PRECONDITION:   the current date can not be 1.
INPUT:		none
PROCESS:	It decrements the current date by one and outputs it.
OUTPUT:		none
POSTCONDITION:	the date is decremented by one

next
PRECONDITION:   the current date can not be 30.
INPUT:		none
PROCESS:	It increments the current date by one and outputs it.
OUTPUT:		none
POSTCONDITION:	the date is incremented by one