[CenterOfMass] Added support to enter a mass explicitly

[nexx512]

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[nexx512]

Sometimes it might be helpful to enter the mass of an object directly. This can be the case if the material is unknown but you know the mass i.e. when reverse engineering parts. Also it is possible to set the mass to zero to ignore certain parts.

I added a checkbox close the the mass input field that ca be checked when the mass should be entered explicitly. In this case the material an density are removed from the body but a Mass property is set.

I also renamed the save button to "Transfer" and edited the tooltip because to me it was very misleading that "Save" stores the properties on the bodies and also opens a save Dialog that I have to close again. From a UI perspective I didn't save anything but something (updating the properties) happened in the background.

[s-quirin]

The idea sounds good! In fact, I shied away from implementing it myself because the dependencies seemed cumbersome to me. Unfortunately I can't even start your macro yet:

self.init_spinMass(self.spinMass, Units.Quantity(g_sel[sol].Mass), parent.unitForM) <class 'AttributeError'>: 'PartDesign.Body' object has no attribute 'Mass'

[nexx512]

Thanks for you comments. I change the source branch in my fork an had to create a new pull request. So I close this pr as it is now superseded by #133