Initial commit of service map stateful processor plugin

[AustinTag]

Issue #, if available:

Description of changes:
Adding initial commit of stateful service map processor plugin

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[kowshikn]

This looks good for the first revision. Just one thought,

            //TODO: Look into faster way to move cursor up N elements
            for(long i=0; i<start; i++) {
                cursor.next();
            }

If we can not optimize this we should do the whole scan and find keyranges once rather than each processor's iterate doing it.