Units: add AngleOfFriction as another parameter with Angle unit

src/App/FreeCADInit.py

@@ -338,7 +338,11 @@ App.Units.Length        = App.Units.Unit(1)
 App.Units.Area          = App.Units.Unit(2)
 App.Units.Volume        = App.Units.Unit(3)
 App.Units.Mass          = App.Units.Unit(0,1) 
-App.Units.Angle         = App.Units.Unit(0,0,0,0,0,0,0,1) 
+
+# Angle
+App.Units.Angle            = App.Units.Unit(0,0,0,0,0,0,0,1)
+App.Units.AngleOfFriction  = App.Units.Unit(0,0,0,0,0,0,0,1)
+
 App.Units.Density       = App.Units.Unit(-3,1)
 
 App.Units.TimeSpan      = App.Units.Unit(0,0,1) 

src/Base/Unit.cpp

@@ -461,7 +461,11 @@ Unit Unit::Length(1);
 Unit Unit::Area(2);
 Unit Unit::Volume(3);
 Unit Unit::Mass(0,1);
-Unit Unit::Angle(0,0,0,0,0,0,0,1);
+
+// Angle, deg
+Unit Unit::Angle           (0,0,0,0,0,0,0,1);
+Unit Unit::AngleOfFriction (0,0,0,0,0,0,0,1);
+
 Unit Unit::Density(-3,1);
 
 Unit Unit::TimeSpan(0,0,1);

src/Base/Unit.h

@@ -93,8 +93,11 @@ public:
     static Unit Length;
     /// Mass unit
     static Unit Mass;
+
     /// Angle
     static Unit Angle;
+    static Unit AngleOfFriction;
+    
     static Unit Density;
 
     static Unit Area;