LHM MODFLOW 6 tracking issue

[JoerivanEngelen]

I've just successfully imported and converted the LHM to a MODFLOW6 model. However, the results still do not make much sense. This issue tracks the fixes required to get some sensible results:

• Add option to bypass ValueError for removed wells during well assigning in to_mf6_pkg #1209
• Too much iMOD5 rivers and drains cells removed during allocation #1210
• iMOD5's recharge rate not converted from mm/d to m/d #1216