[cleanup][femDGOperator] Remove gridSizeInterior here since it's already exported in operator.hh

See merge request !67

exported in operator.hh

[cleanup][_operator] Change to new use of space.storage.

See merge request !66

entries for space.storage.

implement a function that takes a Model and returns the ufl forms that can be put into a scheme:

See merge request !65

    scheme = galerkin( dune.femdg.femDGUFL(Model, space)[0] )
The function returns the [form,dirichletBCs] as first value as used above
and then the individual ufl models and additional terms extracted from the Model class, i.e.,
boundary fluxes, velocity, etc.

add test

Feature/geometry cleanup

See merge request !64

[feature][ScalingLimiter] Allow flexible bounds, i.e. for each component.

See merge request !63

component.

Cleanup/new ufl version

See merge request !62

limiter.

removeIndicator.

[cleanup][Python] Remove imported but unused Python modules.

See merge request !60