Cmesh parameters with rules

[Davknapp]

To enable the usage of the hypercube_pad example I did two things:

Created a class that allows to pass rules to the constructor. Only if the parameter-combination passes these rules the parameter-combination is used to create an example. That way we can easily discribe cases that will crash the creation of the cmesh.

Furthermore, I replaced the geometry - argument in the hypercube_pad example by a flag-parameter use_axis_aligned. Currently, we can not easily use geometries in our tests. Creating a vector of geometries to pass to the constructor is not possible, because of the memory management of the geometries. They use sc memory allocation function and since the geometries are not explicitly destroyed no sc_unref function is called.

All these boxes must be checked by the reviewers before merging the pull request:

As a reviewer please read through all the code lines and make sure that the code is fully understood, bug free, well-documented and well-structured.

General

• The reviewer executed the new code features at least once and checked the results manually

• The code follows the t8code coding guidelines

• New source/header files are properly added to the Makefiles

• The code is well documented

• All function declarations, structs/classes and their members have a proper doxygen documentation

• All new algorithms and data structures are sufficiently optimal in terms of memory and runtime (If this should be merged, but there is still potential for optimization, create a new issue)

Tests

• The code is covered in an existing or new test case using Google Test

Github action

• The code compiles without warning in debugging and release mode, with and without MPI (this should be executed automatically in a github action)

• All tests pass (in various configurations, this should be executed automatically in a github action)

  If the Pull request introduces code that is not covered by the github action (for example coupling with a new library):

  • Should this use case be added to the github action?
  • If not, does the specific use case compile and all tests pass (check manually)

Scripts and Wiki

• If a new directory with source-files is added, it must be covered by the script/find_all_source_files.scp to check the indentation of these files.
• If this PR introduces a new feature, it must be covered in an example/tutorial and a Wiki article.

Licence

• The author added a BSD statement to doc/ (or already has one)

[jmark]

LGTM!