Sketcher: deleteGeometries split

================================

New deleteGeometries function, according to the comment should the same
as deleteGeometry but at a time. However, this is not accurate, as deleteGeometry
deletes any internal geometry associated to the provided GeoIds, whereas
deleteGeometries does not delete that internal geometry.

Solution:
Split deleteGeometries into two different functions:
1) delGeometriesExclusiveList
2) delGeometry

The former will not delete associated internal geometry. It is more efficient, but
it is the resposibility of the caller not to leave internal geometry undeleted.

The latter, implemented in terms of the former, will delete associated internal
geometry too.

As a bonus, the latter will also remove any GeoId duplicates.

src/Mod/Sketcher/App/SketchObject.cpp

@@ -1033,9 +1033,34 @@ int SketchObject::delGeometry(int GeoId, bool deleteinternalgeo)
     return 0;
 }
 
+
 int SketchObject::delGeometries(const std::vector<int>& GeoIds)
 {
     std::vector<int> sGeoIds(GeoIds);
+
+    // if a GeoId has internal geometry, it must delete internal geometries too
+    for(auto c : Constraints.getValues())  {
+        if( c->Type == InternalAlignment ) {
+            auto pos = std::find(sGeoIds.begin(), sGeoIds.end(), c->Second);
+
+            if(pos != sGeoIds.end()) {
+                sGeoIds.push_back(c->First);
+            }
+        }
+    }
+
+    std::sort(sGeoIds.begin(), sGeoIds.end());
+    // eliminate duplicates
+    auto newend = std::unique(sGeoIds.begin(), sGeoIds.end());
+    sGeoIds.resize(std::distance(sGeoIds.begin(), newend));
+
+    return delGeometriesExclusiveList(sGeoIds);
+}
+
+int SketchObject::delGeometriesExclusiveList(const std::vector<int>& GeoIds)
+{
+    std::vector<int> sGeoIds(GeoIds);
+
     std::sort(sGeoIds.begin(), sGeoIds.end());
     if (sGeoIds.empty())
         return 0;
@@ -5392,7 +5417,7 @@ int SketchObject::deleteUnusedInternalGeometry(int GeoId, bool delgeoid)
         if(delgeoid)
             delgeometries.push_back(GeoId);
 
-        int ndeleted = delGeometries(delgeometries);
+        int ndeleted = delGeometriesExclusiveList(delgeometries);
 
         return ndeleted; //number of deleted elements
     }
@@ -5732,7 +5757,7 @@ bool SketchObject::modifyBSplineKnotMultiplicity(int GeoId, int knotIndex, int m
     // Trigger update now
     // Update geometry indices and rebuild vertexindex now via onChanged, so that ViewProvider::UpdateData is triggered.
     if (!delGeoId.empty()) {
-        delGeometries(delGeoId);
+        delGeometriesExclusiveList(delGeoId);
     }
     else {
         Geometry.touch();