Move x-ray lightcone maps into extra_io/EAGLE
The code for the xray lightcones is now only compiled when we have the extra I/O option set to EAGLE and it will be possible to add different sets of maps for other subgrid models.
The code for the xray lightcones is now only compiled when we have the extra I/O option set to EAGLE and it will be possible to add different sets of maps for other subgrid models.