Retain NSInvocation args for double calls.
Added reset_sent_messages for fakes/spies.
Move ARC-incompatible code to implementation files
Doubles correctly match expectations for nil args.
Add and_do() for stubbed methods.
Fix copy paste error in exception copy.
Remove unused variable.
Renamed TypedArgument to ValueArgument
Remove unused method and unused argument names.
Add any(Class) matcher.
Spies correctly record messages sent to self.
Improve error for have_received invalid selector.
Move implementation to mm files.
Add NSString support to be_empty matcher
Work around fiddly ARC errors.

ARC won't compile the templated Stringifier with a block parameter,
since the conditional for for non-objects (which would never run) tries
to output the value to a stream.  ARC thinks the code is converting the
object to a void * and loses its mind.
Work around missing method implementations.

Some methods on certain Cocoa objects (e.g. isSecureTextEntry on
UITextField) return NULL for their method implementations.  Try to
invoke one of those and BOOM!
Remove fix for doubles recording self-invocations.

The fix causes errors in a couple UIKit classes and in KVC.
mark examples as focused based on file name and line number
Support running on iOS 4.x-5.1 (as well as 6.x)

 - Set deployment target to 4.3
 - Avoids using _objc_setProperty_nonatomic_copy which isn't
   available at runtime in iOS < 6.0
Merge pull request #48 from cppforlife/better_focused

ability to run focused specs by putting your cursor on top of an example