Clawpack 5.6.0rc

[Randall J LeVeque]

There's a release candidate for Clawpack 5.6.0 now fully merged into the master branch if anyone would like to take a look and test things out.  

There is also a tar file at

  https://github.com/clawpack/clawpack/releases

that is missing only the latest couple commits, one of which now provides a `clawpack.__version__` attribute.

Recent changes are described at

  http://www.clawpack.org/dev/changes_to_master.html

I created most of this by going quickly through the commits and summarizing some major points, so if anyone want to improve on the description of some change or add more important points, feel free to do a PR on clawpack/doc in the dev branch, or simply send me an email and I'll merge in.

I'm also working on updating a few things in the apps repository.  Other contributions/fixes welcome there too (but not as urgent since that's not distributed with the clawpack release).

I tentatively plan to do the official release Friday or Saturday.

 - Randy

[Randall J LeVeque]

I have released v5.6.0 and will send out a note to claw-users tomorrow.

There are v5.6.0 tags in all the repos, a tar file at 

  https://github.com/clawpack/clawpack/releases/tag/v5.6.0

and at

  https://doi.org/10.5281/zenodo.3237295

updated installation instructions at

   http://www.clawpack.org/installing.html

and release notes at

  http://www.clawpack.org/release_5_6_0.html

I still have to update the docker file on docker hub, and I'm hoping @mandli or @ketch can update Pypi.

Let me know if you spot any problems before announcing in general.  Thanks to everyone who contributed to this!

 - Randy

P.S. the apps repository still needs some updating too.