Support number-style parameters for all inputs.

[jankolkmeier]

As mentioned in #44 it could be nice to support 0x0000-style input for all 16/64 bit parameters for the frame builder besides [0x00, 0x00] and "0000"-style. For 16 bit, we can check for type of the parameter value (is it 'number'?) and then use reader.appendUInt16BE(). For 64 bit params, the buffer-reader would need to be extended to support reader.appendUInt64BE()