Add quotes to header search paths
Clarify -deliverOn: and -subscribeOn:

Specifically, promote -deliverOn: over -subscribeOn:, since the latter
is rarely right.
Merge pull request #541 from lsavino/patch-1

Quote header search path in README
Merge pull request #543 from ReactiveCocoa/better-subscribe-on-docs

Clarify -deliverOn: and -subscribeOn:
Only do work in -rac_description in DEBUG builds
Avoid -rac_description within -description

Since it now doesn't do anything in Debug builds.
Refactor RACCompoundDisposable to use CFArray

Results in a significant performance gain when lots of compound
disposables are in use (and especially nested).
Replace @onExit with try/finally to avoid blocks overhead
Pull disposable arrays out onto the stack for enumeration
Meh, we don't really need exception safety here
Optimize KVO trampoline storage
Merge pull request #549 from ReactiveCocoa/skip-rac-description-in-debug

Only run -rac_description in DEBUG builds
Set iOS deployment target to 5.0
Add SDK requirements to README
Clean-up duplicate entries in ReactiveCocoaTests
Merge pull request #552 from kastiglione/pbxproj-cleanup

Clean-up duplicate entries in ReactiveCocoaTests group
Merge pull request #551 from kastiglione/document-sdk-requirements

Document sdk requirements and set iOS deployment target to 5.0
Merge branch 'master' into more-optimization
Optimize active signals set
Remove unused tearingDown property