add util method for getting all rails zones with current offsets
add util method for getting all rails zones with current offsets

simong/Hilary,ExC0d3/Hilary,Orodan/Hilary,stuartf/Hilary,simong/Hilary,timdegroote/Hilary,nicolaasmatthijs/Hilary,mrvisser/Hilary,timdegroote/Hilary,mrvisser/Hilary,ExC0d3/Hilary,Coenego/Hilary,jfederico/Hilary,Orodan/Hilary,jfederico/Hilary,stuartf/Hilary,nicolaasmatthijs/Hilary