L1: Added boost serializers for L1Parameters objects and their components; implemented an interface for parameters and input data RW

Avoid a problem if the CMake variable ${CPUINFO} is empty.

When compiling one of the test macros the compilation crashed. The reson was
a problem with the generated dictionary. The problem could be solved by
removing an include statement from the header file.

Fix NicaFemto compilation on macosx arm64.
Remove hardcoded GSL search directory and pass the correct brew install
directory which is now taken from the brew command.

Fix KFParticle compilation on macosx arm64.
Add patch which adds an include file which defines _mm_malloc and _mm_free.

When using the commit hash it is possible to check if a download is really
needed. Only in the case the hash has changed the external project command is
executed.