number_hex2bin — Converts an hexadecimal string into a binary string.
binstr = number_hex2binary ( hexstr )
hexstr = "3FE54B3504C6B4A3"; binstr = number_hex2bin (hexstr); expected = "0011111111100101010010110011010100000100110001101011010010100011" // Lower case also works hexstr = "3fe54b3504c6b4a3"; binstr = number_hex2bin (hexstr); expected = "0011111111100101010010110011010100000100110001101011010010100011"