[GPU] Clean Initialization

We clean up the Initialization of the gpu core library.

Delete files:

• GPU/Init27.cu
• PreProcessor/InitAdvectionDifussionCompressibleD3Q7
• PreProcessor/InitAdvectionDifussionIncompressibleD3Q7
• PreProcessor/InitK18K20NavierStokesCompressible

Remaining Initialization:

• PreProcessor/InitK18K20NavierStokesCompressible
• PreProcessor/InitNavierStokesCompressible
• PreProcessor/InitNavierStokesIncompressible
• PreProcessor/InitAdvectionDifussionCompressible
• PreProcessor/InitAdvectionDifussionIncompressible

Deleted:

• Init/Propeller functionality (read input data related to propeller)
• VelocityBCs27/PropellerBC()

Renamed MR: https://git.rz.tu-bs.de/irmb/VirtualFluids_dev/-/merge_requests/295

Deleted MR: https://git.rz.tu-bs.de/irmb/VirtualFluids_dev/-/merge_requests/302

Delete Commit: 5615003f

Last Commit containing everything: 436e905b