SFS Toolbox 1.0.0

First complete 3D version of the SFS Toolbox.

NEWS:

- added references for all driving functions
- streamlined nested conf settings; e.g. now it is no longer neccessary to set
  conf.ir.hcompfile if conf.usehcomp == false
- added WFS driving functions from Völk et al. and Verheijen et al.
- removed secondary_source_number() and xy_grid, because they are no longer
  needed
- enabled pre-equalization filter of WFS as default in SFS_config_example()
- fixed sound_field_mono_sdm_kx()
- Green's function for line sources returns now real values
- correct y-direction of plane waves for 3D NFC-HOA
- updated the test functions in the validation folder
- several small fixes