Moved file out of mako since not needed
Deconstruction of boundary operator

If construction was successful, the boundary operators are now explicitly
deconstructed.
Convenience functions to access sample grids
Constructing options with incompatible basis and result type fails

It wasn't so clear before that. The construction could go through despite the
arguments being incompatible.
Simplifying check for basis and result type compatibility at construction

Boundary operator now relies on the check from Options.
Adding context and boundary operators

Currently implementing only boundary operators from dirichlet tutorial.