first draft of a new post-processor interface.
simple post-processor tests
switched to XCTest
no more test headers, they were dumb anyway.
incremented version
post-processor tests
major reworking of the post-processor subsystem.
code reorg
removed poorly supported / unused measuring functionality from RKURLRequestPromise.
leftover code removal
killed preflight blocks.
less insane logging interface on RKURLRequestPromise.
passing tests
slightly faster locking strategy for RKURLRequestPromises _loadedData ivar + more documentation
refactored useCacheWhenOffline -> offlineBehavior
fiddling
formalized cancelable promises
added RKLazy marker-protocol + More docs on RKPromise
new designated initializer on RKURLRequestPromise
updated RKRequestFactory to use new RKURLRequestPromise initializer + exposed stringifier used for URL parameter bodies