Initial implementation of weak observer support for NSNotificationCenter
Cache method signature while it's still available
WIP for weak mutable set, but need to implement zeroing weak associated objects first \o/
Factor cleanup work into a single targeting proxy class.
Licensing
Deprecate nn_property_copyAttributeList
Document all of the things.
Use reentrant main queue dispatch instead of a hack for notification dispatch.
This ought to resolve the occasional test failure due to poor polling timing.
README updates
Add approximately 25mL of Safety to NNCleanupProxy

Method signatures can't be fetched when the target object is dead, so
they must be cached ahead of time.
Never use exceptions for successful control paths. Even in tests.

And just yesterday I was asking "how can this bite me?" Didn't even
take a whole day.
Be more fatal when selectors are not predeclared.
Private docs
NNMutableWeakSet is finished, with enumerator support.
Whitespace
Not gonna worry about it.
Property should be readonly.