Use separate functions for creating quadrature rule instead of the QuadratureRule constructor

[KristofferC]

#991 (comment)

I think the current way of creating quadrature rules is not ideal. For example we write:

qr = QuadratureRule{RefTetrahedron}(2)

but there are many quadrature rules and it isn't clear which one this creates etc. This was changed by me in #58 and 8 years later I am suggesting we change it back to standard functions like:

create_legendre_quadrature(RefTetrahedron::RefShape, 1::Int)
create_lobotto_quadrature(RefCube::RefShape, 1::Int)

etc. Should be decided before 1.0 I guess.

[fredrikekre]

#1001

[KristofferC]

Pretty sure I only created one issue... Weird.