Changed definition in function wdstr_ens()

* Changed definition in function wdstr_ens():
  * was: 0 radians = south
  * now: 0 radians = north
Changed definition of azimuth in function wdstr_nls()

* Changed definition of azimuth in function wdstr_nls():
  * was: az = 0 radians = south
  * now: az = 0 radians = north
Changed definition of azimuth in function wdstr_nl()

* Changed definition of azimuth in function wdstr_nl():
  * was: az = 0 radians = south
  * now: az = 0 radians = north

* Fixed typo from previous commit