Add various matrix related expression functions (#8603)

Adds a few new Expression functions with the goal to:

- Simplify Placement, Rotation, Vector and Matrix object creation.
- Add new matrix functions for rotation and translation.

src/Base/Quantity.cpp

@@ -271,6 +271,12 @@ bool Quantity::isDimensionless() const
     return isValid() && myUnit.isEmpty();
 }
 
+/// true if it has a specific unit or no dimension.
+bool Quantity::isDimensionlessOrUnit(const Unit& unit) const
+{
+    return isDimensionless() || myUnit == unit;
+}
+
 // true if it has a number and a valid unit
 bool Quantity::isQuantity() const
 {