Method EncodeTerm

Encode metadata as long[] and byte[]. absolute controls whether current term is delta encoded according to latest term. Usually elements in longs are file pointers, so each one always increases when a new term is consumed. out is used to write generic bytes, which are not monotonic.

NOTE: sometimes long[] might contain "don't care" values that are unused, e.g. the pointer to postings list may not be defined for some terms but is defined for others, if it is designed to inline some postings data in term dictionary. In this case, the postings writer should always use the last value, so that each element in metadata long[] remains monotonic.