Fix usgbcf (#1959)

* fix(usg bcf) ksat util3d call --> util2d call

Signed-off-by: Chris Nicol <chris.nicol@groundwaterlogic.com>

* doc(modflow/sfr2) add sfr2 channel_geometry_data to docstring

Signed-off-by: Chris Nicol <chris.nicol@groundwaterlogic.com>

---------

Signed-off-by: Chris Nicol <chris.nicol@groundwaterlogic.com>

flopy/mfusg/mfusgbcf.py

@@ -219,7 +219,7 @@ def __init__(
             locat=self.unit_number[0],
         )
         if not structured:
-            self.ksat = Util3d(
+            self.ksat = Util2d(
                 model,
                 (njag,),
                 np.float32,

flopy/modflow/mfsfr2.py

@@ -182,6 +182,16 @@ class ModflowSfr2(Package):
         Numpy record array of length equal to nss, with columns for each
         variable entered in items 6a, 6b and 6c (see SFR package input
         instructions). Segment numbers are one-based.
+    channel_geometry_data : dict of dicts containing lists
+        Optional. Outer dictionary keyed by stress period (0-based); inner
+        dictionaries keyed by segment number (1-based), for which 8-point channel
+        cross section geometries are desired. Inner dict values are lists of shape
+        (2,8) - with the first dimension referring to two lists: one of 8 XCPT
+        values, and the other of 8 ZCPT values.
+        Example structure: {kper: {segment: [[xcpt1...xcpt8],[zcpt1...zcpt8]]}}.
+        Note that for these to be applied, the user must also specify an icalc
+        value of 2 for each corresponding segment in segment_data for the
+        relevant stress periods.
     dataset_5 : dict of lists
         Optional; will be built automatically from segment_data unless
         specified. Dict of lists, with key for each stress period. Each list