Add converter for iMOD5 LPF data to NPF

[JoerivanEngelen]

Things that need to be done:

• k33 = k * vertical anisotropy
• if ANI (horizontal anisotropy), compute angle

iMOD5 models only contain a rotation in the xy plane, not along the vertical axis.

[JoerivanEngelen]

Merged to feature branch in #1010