T-Spline Mirror mode options needed: ON/Off Remove Bake

[cekuhnen]

Currently

there is only a clear symetry command which removes the function by applying/baking it.

However not always do you want to apply the new geometry.

Sometimes you also just want to turn visibility off so you can look into the object/product.

And when investigated anough you want to turn visibility on again.

So the clear symetry function should have the folllowing options:

Apply (currently implemented)

Remove (result is origninal half model)

Hide/Show (temp turn off/on)