Merge branch 'release/v0.20.0-rc1'
Merge branch 'release/0.20.0'
Drop pre from README.md install instructions
Add another shared object factory method flavor.
Revert "Add another shared object factory method flavor."

This reverts commit 6c842b4fdbd185643280a936b31a950c3032b6ed.
Fix some erroneous comments in the documentation
Fix link breakage due to relative link changes in Github Markdown
Fix CocoaPods build warning "`preferred_dependency` has been renamed to `default_subspec`."
Remove obtaining permanent managedObjectID when adding newly created object to the in memory cache. refs #1329
Style tweak in `dispatch_async` of completion blocks
Fix assertion error while copying RKEntityMapping with connections.
Merge pull request #1342 from chebur/development

Fix assertion error while copying RKEntityMapping having non empty connections.
Bump CocoaPods dep to 0.18.1
Bump all dependencies except for OCMock as the class mocking in 2.1.1 does not seem to work for RK test cases
Bump AFNetworking dependencies to 1.2.1
Port to OCMock 2.1.1 mainline
Add dependency on TransitionKit for state machines
Add state machine for easily implementing concurrent NSOperation subclasses
Add `performBlockAndWait:` invocation to RKFetchRequestManagedObjectCache
Drop parentOperation association and set concurrency limit to 1 on `connectionQueue` in `RKManagedObjectImporter`