Resolve "MultiElasticity should hold multiple MainElasticities"

Closes #213

Should be compiled and tested.

src/elasticity/solvers/ElasticitySolver.cpp

@@ -11,10 +11,14 @@ std::unique_ptr<CardiacSolverT<IElasticity>> GetElasticitySolver() {
 
   if (runtype == "Exact") {
     return std::make_unique<ExactMechanicsSolver>();
-  } else if (runtype == "Klotz") {
+  }
+
+  if (runtype == "Klotz") {
     // Generate KlotzPressureSolver in src/elasticity/solvers/IterativePressureSolver.hpp
     return std::make_unique<KlotzPressureSolver>();
-  } else if (runtype == "Default") {
+  }
+
+  if (runtype == "Default") {
     if (dyn == "Static") {
       // Generate IterativePressureSolver in src/elasticity/solvers/IterativePressureSolver.hpp
       return std::make_unique<IterativePressureSolver>();
@@ -23,4 +27,6 @@ std::unique_ptr<CardiacSolverT<IElasticity>> GetElasticitySolver() {
       return std::make_unique<ElastodynamicTimeIntegrator>(dyn);
     }
   }
+
+  Exit("No solver for RunType " + runtype + " implemented")
 }