* gdb.t00/{default.exp, help.exp}: Account for changes to radix

	* gdb.t00/{default.exp, help.exp}:  Account for changes to radix
	commands.
	* gdb.t16/gdbme.c:  Add and use struct containing arrays of char.
	* gdb.t16/printcmds.exp:  Fix all lines that match "unsigned char *".
	* gdb.t16/printcmds.exp (test_print_char_arrays):  Test printing
	of struct of char arrays.
	* gdb.t00/radix.exp:  New tests for radix commands.