Add print() method, Fix bug in parse() method

public void print()
Prints a multi-line version of the tree
For example, for the Tree:
                            one
                            / \
                           /   \
                         two  three
                         		 /\
                         		/  \
                            four five
                             /\
                            /  \
                          six seven
print method will output the below tree
one
 |  two
 |  three
 |  |  four
 |  |  |  six
 |  |  |  seven
 |  |  five

 Also, fixed a silly curly braces bug in the parse method whcih was
 introduced while cleaning up the code. Else if block which was of
 two lines and which should've been enclosed within {}, was not.