Update Frequency and Time Domain documentation

This includes two points:

* Update the documentation on local WFS as `sound_field_mono_localwfs()` is now deprecated.
* Repeat the structure of WFS, NFC-HOA, LWFS for the Time Domain

See:
http://matlab.sfstoolbox.org/en/latest/frequency-domain/
http://matlab.sfstoolbox.org/en/latest/time-domain/