Fix a bunch of warnings (#2254)

* fix a couple warnings

* fix a bunch of warnings (mostly unused variable)

* fix a bunch of warnings and simplify params

* Special assert so that variables aren't seen as unused

* fix tutorial

* undo erroneous line removal

* ASSERT -> IGL_ASSERT

* VSC ❄️ doesn't realize MAX_DEPTH is conts

tutorial/902_VectorParallelTransport/main.cpp

@@ -45,7 +45,7 @@ int main(int argc, char * argv[])
   //Compute vector Laplacian and mass matrix
   Eigen::MatrixXi E, oE;//Compute Laplacian and mass matrix
   SparseMat vecL, vecM;
-  igl::cr_vector_mass(V, F, E, oE, vecM);
+  igl::cr_vector_mass(V, F, E, vecM);
   igl::cr_vector_laplacian(V, F, E, oE, vecL);
   const int m = vecL.rows()/2; //The number of edges in the mesh