CocoaPods installation guide in README.

Fixes #60.
Merge pull request #77 from wlue/master

CocoaPods installation guide in README.
Fix for crash when having a library that looks like a NSURLConnectionDelegate, like PubNub (which does responds to the 2 selectors injectIntoAllNSURLConnectionDelegateClasses checks on, but does not on currentRequest method.
Don't crash when exchangeSubviewAtIndex:withSubviewAtIndex: is called with invalid indices.
Fix view hierarchy debugging with complex key paths (multiple components).
Also guard against exchangeSubview indices being negative. 

The UIView method doesn't crash in this case either.
Merge pull request #80 from ryanolsonk/defensiveExchangeSubviews

Fix crash in swizzled exchangeSubviewAtIndex:withSubviewAtIndex:
Merge pull request #79 from peterwilli/master

Fix for crash when having a library that looks like a NSURLConnectionDelegate, like PubNub
Fix only building active arch in debug.
Bump SR to master.
Merge pull request #85 from square/kve/fix-building-only-active-arch-for-debug

Fix only building active arch in debug.
Merge pull request #81 from ryanolsonk/multiComponentKeyPathFix

Fix view hierarchy debugging with complex key paths
Add note for pulling master on CocoaPods
Merge pull request #99 from wlue/cocoapods

Add note for pulling master on CocoaPods
Update README for v0.3.1
Merge pull request #97 from wlue/v0.3.1

Update README for v0.3.1
XCode 5.1 warnings.
Merge pull request #104 from wlue/master

XCode 5.1 warnings.
Turn ONLY_ACTIVE_ARCH back off.
Merge pull request #107 from square/puls/only-active-arch

Turn ONLY_ACTIVE_ARCH back off.