Merge jspahrsummers/RxSwift@9f60589ceba10a6e594e618034ab41bfad465318
Disable automatic unit test builds for now #yolo
Add Swift sources, with generated bridging header
Bump deployment targets for Swift
Merge pull request #1307 from ReactiveCocoa/bump-deployment

Bump OS X deployment target to 10.8
Conflicts:
	ReactiveCocoaFramework/ReactiveCocoa.xcodeproj/project.pbxproj
	ReactiveCocoaFramework/ReactiveCocoaTests/RACReplaySubjectSpec.m
Import all of RAC into Swift
Bridge RACSignal <> Observable
Fix up RACSignal boolean operators for Swift
Rename Observable -> Signal

@joshaber won’t let me merge this otherwise. :cry:
Moved flatten and dematerialize inside stream
Minor stylistic fixes
Move more functions into Stream with TypeEquality
Merge pull request #1384
Remove MutableBox, make Box final

++immutability
Mark AsyncBuffer as final
Mark all Disposable implementations as final
Mark all signal/sequence methods as final

Subclasses should not be able to change the contract of these methods.
Fix naming of private properties in AsyncBuffer
Mark properties as final too
Make Refl into a struct

/cc @maxpow4h