added identifier to speaker
Merge branch 'master' of https://github.com/TEDxCT/tedx_ios

Conflicts:
	TEDxCT/Models/CoreData/TEDSpeaker.h
	TEDxCT/Models/CoreData/TEDSpeaker.m
	TEDxCT/TEDxCT.xcdatamodeld/TEDxCT.xcdatamodel/contents