Add unit tests for DispatchChains
Add unit tests for DispatchChains

neiljerram/felix,kasisnu/calico,beddari/calico,TrimBiggs/calico,neiljerram/felix,alexhersh/calico,neiljerram/felix,TrimBiggs/calico,beddari/calico,ocadotechnology/calico,anortef/calico,ocadotechnology/calico,matthewdupre/felix,Metaswitch/calico,matthewdupre/felix,alexhersh/calico,neiljerram/felix,kasisnu/calico,Metaswitch/calico,anortef/calico