working on the reverse iptag multicast source model
Merge branch 'master_pop_table_refactor_to_pluggable' of https://github.com/SpiNNakerManchester/sPyNNaker into master_pop_table_refactor_to_pluggable
Merge branch 'master_pop_table_refactor_to_pluggable' of https://github.com/SpiNNakerManchester/sPyNNaker into master_pop_table_refactor_to_pluggable