refs #291, bearing

* method to calculate bearing between coordinates
* Helper methods to normalize degrees (0..360deg), e.g. -10deg -> 350deg

src/blackmisc/mathematics.h

@@ -144,6 +144,12 @@ namespace BlackMisc
              */
             static double rad2deg(double radians);
 
+            /*!
+             * \brief Normalize to 0..360 degrees
+             * \param degrees
+             * \return
+             */
+            static double normalizeDegrees(double degrees);
 
         private:
             /*!