VC2017/Qt 5.12.1 - Fix 64Bit Build Problem

... with windows / VC2017 / 64Bit the code does not build / cannot resolve a overwritten function when using QT 5.12.1
... adding the newly introduced function similar to the other function resolves the compile problem

src/FileIO/LocationInterpolation.cpp

@@ -243,6 +243,11 @@ geolocation GeoPointInterpolator::Interpolate(double distance)
     return DistancePointInterpolator::Interpolate(distance).togeolocation();
 }
 
+bool GeoPointInterpolator::GetBracket(double &d0, double &d1)
+{
+    return DistancePointInterpolator::GetBracket(d0, d1);
+}
+
 void GeoPointInterpolator::Push(double distance, geolocation point)
 {
     DistancePointInterpolator::Push(distance, point.toxyz());

src/FileIO/LocationInterpolation.h

@@ -492,6 +492,7 @@ public:
     GeoPointInterpolator() : DistancePointInterpolator() {}
 
     geolocation Interpolate(double distance);
+    bool GetBracket(double &d0, double &d1);
 
     void Push(double distance, geolocation point);
 };