Fine tune previous patch

Stefan Geschwentner · mcostalba · commit 8ca80cb0f1bb · 2013-12-27T18:46:49.000+01:00
Passed short TC
LLR: 2.95 (-2.94,2.94) [-1.50,4.50]
Total: 18331 W: 3608 L: 3453 D: 11270

And scored above 50% on a very long test in long TC
LLR: -2.97 (-2.94,2.94) [0.00,6.00]
Total: 51533 W: 8181 L: 8047 D: 35305

bench: 7335588
diff --git a/src/pawns.cpp b/src/pawns.cpp
@@ -58,7 +58,7 @@ namespace {
     S(34,68), S(83,166), S(0, 0), S( 0, 0) };
 
   // Bonus for file distance of the two outermost pawns
-  const Score PawnsFileSpan = S(0, 10);
+  const Score PawnsFileSpan = S(0, 15);
 
   // Weakness of our pawn shelter in front of the king indexed by [rank]
   const Value ShelterWeakness[RANK_NB] =
