Implement Internal Cache

[atmaxinger]

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[kodebach]

Suggested change

	ksAppend (keysForSpec, dataKs);
	ksAppend (keysForSpec, fromInternalCache);
	ksAppend (keysForSpec, fromInternalCache);
	ksAppend (keysForSpec, dataKs);

Isn't this the wrong way around? In Step 18, fromInternalCache is appended first

[kodebach]

Suggested change

	if (fromInternalCache) ksDel (fromInternalCache);
	ksDel (fromInternalCache);

ksDel (NULL) is a no-op

[kodebach]

I think this might be easier with ksFindHierarchy and a loop of ksAppendKey and performance-wise it makes no difference since ksAppend is also a loop of ksAppendKey right now (but you avoid allocating all these temporary KeySets).