make "orientation" module part of damask python interface

lib/damask/__init__.py

@@ -5,6 +5,7 @@ from .environment import Environment      # only one class
 from .asciitable  import ASCIItable       # only one class
 from .config      import Material         # will be extended to debug and numerics
 from .colormaps   import Colormap, Color
+from .orientation import Vector3, Quaternion
 #from .block       import Block           # only one class
 from .result      import Result           # one class with subclasses
 from .geometry    import Geometry         # one class with subclasses
@@ -51,4 +52,4 @@ except (ImportError,AttributeError) as e:
                                           ):
     sys.stderr.write('\nWARNING: Core module (Fortran code) not available, \n'\
                      'try to run setup_processing.sh or compile_CoreModule.py\n'\
-                     'Error Message when importing core.so: %s\n\n'%e)
+                     'Error message when importing core.so: %s\n\n'%e)

lib/damask/orientation.py

@@ -244,6 +244,12 @@ class Vector3:
                         self.z - d * normal[2]])
 
     def inSST(self,symmetry):
+      '''
+      Determination of disorientations follow the work of A. Heinz and P. Neumann:
+      Representation of Orientation and Disorientation Data for
+      Cubic, Hexagonal, Tetragonal and Orthorhombic Crystals
+      Acta Cryst. (1991). A47, 780-789
+      '''
       return {'cubic':       lambda R: R.inFZ('cubic')       and R.x >= R.y and R.y >= R.z and R.z >= 0.0,
               'hexagonal':   lambda R: R.inFZ('hexagonal')   and R.x >= math.sqrt(3)*R.y and R.y >= 0.0 and R.z >= 0.0,
               'tetragonal':  lambda R: R.inFZ('tetragonal')  and R.x >= R.y and R.y >= 0.0 and R.z >= 0.0,