Rename Aff

[dpsanders]

Aff is the true affine arithmetic.

Affine is the combined affine--interval arithmetic proposed by Rump that also keeps track of the interval range using standard interval arithmetic and takes the intersection of the two.

For real calculations you probably want Affine, although it will be a bit (or much?) slower.
But the names are not ideal.

cc @mforets

[mforets]

Ok, i have to do some studying and reading first :p but, yeah Aff and Affine are too similar.. One possibility:

abstract type AbstractAffineForm end

struct Affine <: AbstractAffineForm . . . end #  "canonical", current "Aff"
struct MixedAffine <: AbstractAffineForm . . . end #  current "Affine"

If it turns out that only the mixed affine form is of interest in calculations, perhaps:

struct BasicAffine <: AbstractAffineForm . . . end #  "canonical", current "Aff"
struct MixedAffine <: AbstractAffineForm . . . end #  current "Affine"
const Affine = MixedAffine # export convenience alias

[dpsanders]

I like that second solution!