2748 mat sym print

http://stackoverflow.com/questions/20885374/sympy-dense-display-of-matrices-of-arbitrary-size

->As mentioned in issue #2748 there is no method in matexp.py to print the symbolic representation of a MatrixSymbol with arbitrary size,ex. m rows and n columns.
->Implemented a function matsym_print to print matrix symbols with symbolic number of rows or columns.