0.4.0 release

[kinnala]

Sort of "1.0.0 prerelease". Hopefully one of the last ones.

[gdmcbain]

Re 1.0.0: I'm thinking that there are going to be a few changes soon over at meshio nschloe/meshio#619 nschloe/meshio#568 which might affect i/o here #261 #271 #291. I'm not sure how that affects the roadmap. Is i/o separate enough that it won't?

[nschloe]

You can always depend on "meshio < 4", its API is stable across major versions. You can then make the switch whenever you like.

[gdmcbain]

Ta. Yes, no, I'm not so much worried about adapting here to the changes scheduled thus far for meshio 4 (transposition of keys of cell_data), that'll be straightforward; it's more that I'm hoping to take advantage in scikit-fem 1 of some of the other advances that might make it in like a more complete implementation of XDMF 3 or the rolling out of cell_sets to formats other than MED. Those will permit substantial improvements here.

[nschloe]

Ah cool. Let's make sure that we get all of this implemented in meshio then!