Add some additional tests for SDC time-integration techniques. Currently, SDC time-integration schemes are only tested through
TimeIntegrationDemo.cpp. However, this does not offer a complete coverage of the schemes notably in terms of time-dependent boundary condition and accuracy and convergence.
Include SDC tests using the ADR solver. This allows a full coverage of explicit, implicit, and IMEX SDC schemes.
Please suggest any people who would be appropriate to review your code.
Please add any other information that could be useful for reviewers.