E3-1009: Import makefile
This MR imports the (conda) makefile from https://gitlab.esss.lu.se/beam-diagnostics/bde/modules/xtpico. There is an associated MR for the removal of the makefile from that repository.
This MR is primarily for @hinkokocevar and @nicklasholmberg2 to review/approve/merge.
Edited by Anders Lindh Olsson