Merge branch 'master' into clusterMergeMaster12

fixes minor merge conflicts

looks good:

Score of cluster vs master: 15 - 1 - 134  [0.547] 150
Elo difference: 32.5 +/- 17.5, LOS: 100.0 %, DrawRatio: 89.3 %

for 4 threads against 4x4 threads at 10+0.1s

src/cluster.cpp

@@ -33,6 +33,7 @@
 #include "tt.h"
 #include "timeman.h"
 
+namespace Stockfish {
 namespace Cluster {
 
 // Total number of ranks and rank within the communicator
@@ -450,6 +451,7 @@ uint64_t TT_saves() {
 }
 
 
+}
 }
 
 #else
@@ -457,6 +459,7 @@ uint64_t TT_saves() {
 #include "cluster.h"
 #include "thread.h"
 
+namespace Stockfish {
 namespace Cluster {
 
 uint64_t nodes_searched() {
@@ -474,6 +477,7 @@ uint64_t TT_saves() {
   return Threads.TT_saves();
 }
 
+}
 }
 
 #endif // USE_MPI