Feature/proximal newton solver

Introduce a Riemannian Proximal-Newton Solver as an alternative for the Trust-Region Solver. Also add 3 cleanup commits.

problems/film-on-substrate.parset

@@ -9,10 +9,10 @@ structuredGrid = true
 lower = 0 0 0
 upper = 200 100 200
 
-elements = 10 5 5
+elements = 4 2 2
 
 # Number of grid levels, all elements containing surfaceshell grid vertices will get adaptively refined
-numLevels = 2
+numLevels = 1
 
 # When starting from a file, the stress-free configuration of the surfaceShell is read from a file, this file needs to match the *finest* grid level!
 startFromFile = false
@@ -26,7 +26,7 @@ gridDeformation="[1.3*x[0], x[1], x[2]]"
 #  Boundary values
 #############################################
 
-problem = cantilever
+dirichletValues = identity-dirichlet-values
 
 ###  Python predicate specifying all Dirichlet grid vertices
 # x is the vertex coordinate
@@ -34,7 +34,7 @@ dirichletVerticesPredicate = "x[0] < 0.01"
 
 ###  Python predicate specifying all surfaceshell grid vertices, elements conataining these vertices will get adaptively refined
 # x is the vertex coordinate
-surfaceShellVerticesPredicate = "x[2] > 199.99"
+surfaceShellVerticesPredicate = "x[2] > 199.99 and x[0] > 49.99 and x[0] < 150.01"
 
 ###  Python predicate specifying all Neumann grid vertices
 # x is the vertex coordinate
@@ -60,7 +60,7 @@ numHomotopySteps = 1
 tolerance = 1e-3
 
 # Max number of solver steps
-maxSolverSteps = 300
+maxSolverSteps = 1
 
 # Measure convergence
 instrumented = 0
@@ -70,7 +70,7 @@ instrumented = 0
 #############################################
 
 # initial regularization parameter
-initialRegularization = 10000000000
+initialRegularization = 1000000
 
 #############################################
 #  Solver parameters specific for trust-region solver using multigrid solver 
@@ -106,7 +106,7 @@ baseTolerance = 1e-8
 #   Material parameters
 ############################
 
-energy = stvenantkirchhoff
+energy = mooneyrivlin
 
 ## For the Wriggers L-shape example
 [materialParameters]
@@ -122,13 +122,7 @@ surfaceShellParameters = surface-shell-parameters-1-3
 mu_c = 0
 
 # Length scale parameter
-L_c = 0.2 
-
-# Curvature exponent
-q = 2
-
-# Shear correction factor
-kappa = 1
+L_c = 0.2
 
 b1 = 1
 b2 = 1