Requested Property Relocation (CamberAtMidspan)

The property "CamberAtMidspan" is currently located in Pset_PrecastConcreteElementGeneral.
However, camber information is relevant to most/all beams regardless of material and construction type.
Would request moving "CamberAtMidspan" to Pset_BeamCommon

Another option is to create a new Pset_BeamCamber and relocate all possible related properties to this Pset including:
- CamberAtMidpsan
- ChordLength (length of chord from arc formed by cambered beam along axis at top of beam)
- WhenMeasured (point in time [e.g., 10 years, 20 years] or phase in process [e.g., fabrication, placement, loaded] - especially relevant to prestressed/precast concrete

The idea is to provide basic Camber info for all beams, without getting into the weeds with requirements that could be more thoroughly represented in the IfcStructuralCurveMember as noted in documentation for [IfcBeam](https://ifc43-docs.standards.buildingsmart.org/IFC/RELEASE/IFC4x3/HTML/lexical/IfcBeam.htm).