Disregard a whole match list for too distant words
Disregard a whole match list for too distant words

This improves the performance for long sentences, in which such distant
words exist - redundant match-list traversals and length_limit
comparison per match try, are prevented.

Length limit skipping stats:
en/corpus-fixes.batch:
  62438 ML lc
2398072 ML no skip
   6407 ML w
2147873 MR no skip
 186632 MR rc
   2044 MR w
en/corpus-fix-long.batch (without the last 3 sentences):
6048981 ML lc
34675268 ML no skip
 169884 ML w
37528934 MR no skip
8659016 MR rc
  32219 MR w

MadBomber/link-grammar,linas/link-grammar,opencog/link-grammar,ampli/link-grammar,opencog/link-grammar,MadBomber/link-grammar,linas/link-grammar,ampli/link-grammar,ampli/link-grammar,MadBomber/link-grammar,ampli/link-grammar,linas/link-grammar,linas/link-grammar,MadBomber/link-grammar,ampli/link-grammar,ampli/link-grammar,ampli/link-grammar,linas/link-grammar,ampli/link-grammar,MadBomber/link-grammar,opencog/link-grammar,MadBomber/link-grammar,ampli/link-grammar,opencog/link-grammar,linas/link-grammar,MadBomber/link-grammar,opencog/link-grammar,linas/link-grammar,linas/link-grammar,MadBomber/link-grammar,opencog/link-grammar,opencog/link-grammar,opencog/link-grammar,opencog/link-grammar,linas/link-grammar