Update RKMapping.h

importing foundation to get rid of swift complier error
fixes #1995
added test for https://github.com/RestKit/RestKit/issues/2000
Merge pull request #1996 from valeriomazzeo/1995-localObjectsFromFetchRequests

fixes #1995 - RKMananagedObjectRequestOperation:localObjectsFromFetchRequests parameter not used
fixes #2000
better fix for #2000 #2001 #1990
Merge pull request #2001 from valeriomazzeo/2000-string-identifier

fixes #2000 #1990
extended RKObjectMappingMatcher capabilities with a RKKeyPathClassObjectMappingMatcher class
following #1355
fixed bug caused by #2001
Merge pull request #2003 from valeriomazzeo/search-array-indexing-strings-numbers

following #1355 - Implemented indexing on NSArray of NSString and NSNumber
removed unnecessary check
Merge pull request #2002 from valeriomazzeo/RKKeyPathClassObjectMappingMatcher

extended RKObjectMappingMatcher capabilities with a RKKeyPathClassObject...
Merge branch 'patch-1' of https://github.com/Jian130/RestKit into Jian130-patch-1
Merge branch 'Jian130-patch-1' into development
Allow for the Testing and CoreData subspecs without the Search subspec
Merge pull request #2007 from RestKit/testing-with-core-data-without-search

Allow for the Testing and CoreData subspecs without the Search subspec
Ignored undeclared selector warning for search indexer RKTestFactory code
Bump version to v0.23.3
Merge branch 'release/0.23.3' into development