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This is a light-weight c++ only geometry extension to enable migration of information that was stored within
the Part WB and should be migrated to another WB (for example Sketcher WB)
It is designed so that a single extension can migrate different types of data (current and future).
When new data needs to be migrated, first a new enum bit is to be added to the class enum and new data members are to
be added to store the information within GeometryMigrationExtension class.
In the Restore() function restoring the data to be migrated, a GeometryMigrationExtension extension is added to the
geometry to be migrated with the data information and the corresponding enum bit set.
In the object to receive the migration data, onDocumentRestored() it is checked whether an extension of type
GeometryMigrationExtension is present, if yes, it is checked whether a bit used for migration is set and, if yes,
the data is retrieved and the GeometryMigrationExtension extension (preferably) removed from the Geometry object.
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Encapsulate Part::Geometry data member copy process in a single function (copyNonTag).
Part::Geometry derived classes need not know the specifics of the data member of Part::Geometry.
Change the delegation of the copy of extensions from clone() to copyNonTag. Because clone() relies on
copy() and now copy() of Part::Geometry data member relies on copyNonTag(), there is no actual change
to the clone() functionality, but the copy() funcionality gains the copy of the extensions via copyNonTag().
This commit adds SVG files with icons for these commands. Also, it makes the necessary changes on CommandDoc.cpp, CommandWindow.cpp, CommandStd.cpp and resource.qrc files.
At the moment one has to specify the LineGroup as string. But one doesn't know what groups exist. So one has to check the Wiki, learn there where the groups are defined and then open the definition file with a text editor.
This PR simplifies this by reading the existing groups out of the definition file and fill the combobox accordingly.
It also give the user info what the selected LineGroup defines via the tooltip.
A nice side effect is that no typos can occur since you don't have to enter the LineGroup name as text.
