Add forktest target to the Xcode project.
Write design for fork safety and cross-reference from the code.
Update release notes.
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Change: 193760
When CONFIG_THREAD_SINGLE is defined, use the generic lock module rather than compiling out all lock calls via lock.h. (Otherwise test cases that check LockIsHeld will fail.)
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Change: 192254
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Place a cross-reference by each assertion the appears in the manual, to assist in keeping the manual up to date.
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Change: 192097
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