Version 10

Updated tests are pending.

- The concrete RKURLRequestPromiseCacheManager has been refactored into RKFileSystemCacheManager. Optional (on by default) Compatibility aliases have been provided that will be removed in the future.
- RKFileSystemCacheManager sheds RKURLRequestPromiseCacheManager's bucket concept in favor of a single space-managed cache. Legacy method is retained (with deprecation marker) but no longer returns distinct objects.
- RKFileSystemCacheManager adds data expiration (7 days untouched).
- Added new RKRequestFactory class which will aid in the repetitive business of vending RKURLRequestPromise objects.
- Added shorter init methods to RKURLRequestPromise.
- RKDictinoaryMap has been obsoleted.
- The unsafe RKObjectRetain/Release/Autorelease functions have been deprecated and will be obsoleted in the next version.
Bug fix
Improvements

- RKDictionaryToURLParametersString now includes an optional value stringifier parameter that allows clients to control how values are represented in URL parameter strings.
- RKRequestFactory now has separate cache managers for read and write requests.
- RKRequestFactory now takes type information for POST/PUT payloads (now called bodies) that allow it to accept plain data or a URL parameters or a JSON object.
Bug fix in RKFileSystemCacheManager + Live Nation Labs contributing RKImageLoader.