made some resource buff functions member-wise const
made some resource buff functions member-wise const

gidden/cyclus,gidden/cyclus,rwcarlsen/cyclus,gidden/cyclus,Baaaaam/cyclus,rwcarlsen/cyclus,hodger/cyclus,rwcarlsen/cyclus,mbmcgarry/cyclus,mbmcgarry/cyclus,hodger/cyclus,hodger/cyclus,hodger/cyclus,mbmcgarry/cyclus,hodger/cyclus,rwcarlsen/cyclus,mbmcgarry/cyclus,gidden/cyclus,Baaaaam/cyclus,Baaaaam/cyclus