support setting a single element by names/keys

[aplavin]

As I understand, currently there is no way to set a single value specified by names and keys, as in Nc(obs='a', iter=20, :) .= 1000. This PR adds makes it possible.

It makes named dimensions work the same way as unnamed ones: add : when indexing in order to make a view.

[aplavin]

nightly test failures seem unrelated

[aplavin]

bump!

[aplavin]

bump...

[aplavin]

bump...

[aplavin]

bump! @mcabbott

[aplavin]

Bump @mcabbott

[aplavin]

Bump @mcabbott

[aplavin]

bump!

[aplavin]

semi-yearly bump @mcabbott :)

[aplavin]

Not sure what's the best way forward here: the package definitely seems maintained, but just very minimally. This and a few other simple small PRs are hanging for a long time without any response.

What could be done to improve the current situation, especially if you @mcabbott don't have too much time for this?

• transfer somewhere like JuliaArrays
• fork as AxisKeys2 (or whatever name)
• make another package AxisKeysExtra (that continues using AxisKeys types and functions) with these and other reasonable changes/extensions

Short-term, I'm leaning towards the last approach, maybe will register such a package soon. Over time, I gathered several other updates (most recently, Makie extension), just didn't bother making new PRs for them while these are hanging anyway.

[aplavin]

All failures seem unrelated (they are due to #148), so I guess will merge...