refs #403 add default constructors to CAvionicsBase and CPhysicalQuantity

The rationale behind this is that QtMetaType complains if there
is no default constructor.

src/blackmisc/aviation/avionicsbase.h

@@ -23,6 +23,10 @@ namespace BlackMisc
         protected:
             QString m_name; //!< name of the unit
 
+            //! Default constructor
+            //! \todo Remove as part of MS' CValueObject refactoring
+            CAvionicsBase() : m_name("empty") {}
+
             //! \brief Constructor
             CAvionicsBase(const QString &name) : m_name(name) {}
 

src/blackmisc/pq/physicalquantity.h

@@ -245,6 +245,11 @@ namespace BlackMisc
             virtual void setPropertyByIndex(const CVariant &variant, const BlackMisc::CPropertyIndex &index) override;
 
         protected:
+
+            //! Default constructor
+            //! \todo Remove as part of MS' CValueObject refactoring
+            CPhysicalQuantity() : m_value(0.0), m_unit(MU::nullUnit()) {}
+
             //! Constructor with double
             CPhysicalQuantity(double value, const MU &unit);