++xcconfigs
Don't automatically build tests with main target
Rename boolean operators for Swift compatibility
Add other headers to umbrella (required for modules)
Define a module for ReactiveCocoa-Mac too
Merge remote-tracking branch 'origin/master' into xcode6
Revert "Rename boolean operators for Swift compatibility"

This reverts commit a2d8c1b75902dcd695862ddcf881b05bedd86c2e.
Failing unit test to expose thread-unsafe implementation of -[RACSerialDisposable disposable].
Reimplement RACSerialDisposable with OSSpinLock rather than OSAtomic in order to fix -disposable method to be thread safe.
Formatting.
More code review feedback.
Switch to use CFBridgingRelease.
Bump Specta to wip-0.3
Basic tests for instantiating/observing a Signal
Add basic test for Signal.interval
Test pipeWithInitialValue
Test optional unwrapping operators
More code review feedback.
Use curried methods for observation callbacks
Test signal merging and switching