Document api modules and require explicit imports of API submodules

src/ifcopenshell-python/ifcopenshell/api/grid/__init__.py

@@ -16,9 +16,17 @@
 # You should have received a copy of the GNU Lesser General Public License
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
+"""Manages grid and grid axes
+
+A grid in IFC may contain two or more axes running in two or more directions.
+"""
+
+from .. import wrap_usecases
 try:
     from .create_axis_curve import create_axis_curve
 except ModuleNotFoundError as e:
     print(f"Note: API not available due to missing dependencies: grid.create_axis_curve - {e}")
 from .create_grid_axis import create_grid_axis
 from .remove_grid_axis import remove_grid_axis
+
+wrap_usecases(__path__, __name__)