Clear ui for flip line tool

Provide different icons for interactive and batch modes
Select mode via drop down
Disable tools if active layer has no or unknown geometry
Create abstract classes for single and dual tools
[FEATURE] make multi to single tool dual mode
Include point in DualTool's default geometryType

exclude unknown geometry type
Harmonize function names of abstract tools
Add tooltip to dual tool
Make DtFlipLine a child of DtDualTool
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Create new abstract subclasses of DtDualTool

Make tools subclass of DtDualToolSelectFeature
Make DtFillRing a subclass of DtDualToolSelectVertex
Merge deleteRings into dtutils
Change icon
Make DtFillGap a subclass of DtDualToolSelectVertex
Renew tooltips
Change icons
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Create two abstract classes for a single button/edit tool
Make DtProlongLine a subclass of DtSingleEditTool
Make DtCutWithPolygon a subclass of DtSingleButton