Dirichlet boundary values for the L-shape example

[[Imported from SVN: r9900]]

wriggers-l-shape-dirichlet-values.py

+class DirichletValues:
+    def __init__(self, homotopyParameter):
+        self.homotopyParameter = homotopyParameter
+
+    def deformation(self, x):
+        # Clamp the L-shape in its reference configuration
+        return [x[0], x[1], 0]
+
+    def orientation(self, x):
+        rotation = [[1,0,0], [0, 1, 0], [0, 0, 1]]
+        return rotation