ALUT: Time units

I've just recognized a minor aesthetical issue in the ALUT API:
alutBufferCreateWaveform expects the duration in seconds as an ALfloat, but
alutMicroSleep expects microseconds as an ALuint. Using different time units
in the same API is a bit ugly IMHO, so an option would be removing
alutMicroSleep and adding:

   ALboolean alutSleep ( ALfloat seconds );

What do people think about this change? Not really a big change, but it
makes ALUT a bit more consistent... In addition, the floating point value
drastically enlarges the range of possible durations (at the cost of
accuracy for large durations, of course).

Cheers,
   S.