Fix main Makefile after the merge.
Fix main Makefile after the merge.


Former-commit-id: cbfd092d96c9190c968552b9cd4140fe5424cff5
wkrzemien/j-pet-framework,wkrzemien/j-pet-framework,wkrzemien/j-pet-framework,wkrzemien/j-pet-framework,alexkernphysiker/j-pet-framework,JPETTomography/j-pet-framework,alexkernphysiker/j-pet-framework,JPETTomography/j-pet-framework,alexkernphysiker/j-pet-framework,wkrzemien/j-pet-framework,JPETTomography/j-pet-framework,alexkernphysiker/j-pet-framework,alexkernphysiker/j-pet-framework