general updates

[markmbaum]

I happened to be looking for some kind of frozen/immutable/read-only array wrapper on the same day as the discussion in #8 started.

Because @bkamins says the package hasn't been maintained, I made a bunch of changes. The module source is nearly identical, but I updated the tests, readme, and dependencies.

• I consolidated and reorganized the tests. Was there a particular reason for testing with sparse arrays? I considered it, then removed the sparse array testing. It seemed oddly specific if the module covers any AbstractArray.
• I updated the readme to explain the module more and give an example.
• I reformated the source module.
• The automatic tests are now in a GitHub action, which runs automatically on all pushes (happy to change this). I removed the other coverage and build status checks.

[bkamins]

Thank you! Do you want me to bump version and tag a release?

[markmbaum]

Yes, please! Although it looks like version 0.2.0 is not registered yet: https://juliahub.com/ui/Packages/General/ReadOnlyArrays

It should be sufficient to trigger a release.

[MilesCranmer]

Could you please make a new release @bkamins? Would love to use this (just found it).

Edit: wait, pause for the issue I found in #11