Link swiftz-core (from maxpow4h/swiftz) into RAC
Replace things with swiftz_core equivalents
Add tryMap overload that deals with Results
++swiftz
Merge branch 'swift-development' into add-swiftz-core

Conflicts:
	ReactiveCocoa.xcodeproj/project.pbxproj
	ReactiveCocoa/Box.swift
	ReactiveCocoa/Consumer.swift
	ReactiveCocoa/Identity.swift
	ReactiveCocoa/Producer.swift
	ReactiveCocoa/Result.swift
Merge pull request #1406 from ReactiveCocoa/add-swiftz-core

Add swiftz_core