before only one channel side could have a velocity boundary condition (bc). When setting a bc at a second side, the first bc was overwritten.

(cherry picked from commit daa787a3)

(cherry picked from commit f1a5c1bb7a77997757cf4fa85910745ad9d21534)

changed the naming of the missing Classes (Strategies) and added the chimera kernel from the open source code

simplified the kernel factory infrastructure by omit the enum (Kerneltype) -> adding new kernels to the factory should be straightforward now

As the cuda warnings are different on each platform and super badly documented, we switch to suppress all warnings for the GridGenerator.

Fix various msvc compiler warnings. With msvc the compiler flags are explicit passed to nvcc with -Xcompiler.