* Add a implicit-typed list reader to CCCC utils since we have 3
  implementations, and growing

* Make CCCC file names into module-level constants to reduce strings

* Reduce pointless mesh computations during reactor init

* Promote coverage to main requirements file since it is required if you
  activate the framework "coverage" setting.

This is another step towards a better cccc submodule.

* Put all cccc modules in new subpackage for clarity about what's cccc

* Added more docs and examples

This did not go so far as to add a consistent public interface on all
cccc DataContainers so users don't have to use the streams.

This makes all non-scalar CCCC data ndarrays for consistency.

Also updated new NhfluxStreams to deal with VARIANT options.