piotrows/advectionHPCtester: Advection HPC tester: MPDATA eDSL

This release serves as a reference to the article submitted to GMD titled: "Parflow 3.9: development of lightweight embedded DSLs for geoscientific models." It consists of a simple implementation of the MPDATA family of schemes with performance portability achieved via eDSL approach. Its primary aim is to support the development of the eDSL techniques. The code is released under GNU LPGL.