ENH: extend bitSet functionality

- num_blocks(), test_set() as per boost
- broadcast(), reduceAnd(), reduceOr() to simplify parallel operations
- matrix-like output for PackedList::writeList()

BUG: Pstream::broadcastList() missing resize on sub-ranks

- latent bug since it was unused in any OpenFOAM code

applications/test/parallel-comm3a/Test-parallel-comm3a.cxx

@@ -79,7 +79,7 @@ int main(int argc, char *argv[])
 
     #include "setRootCase.H"
 
-    if (!Pstream::parRun())
+    if (!UPstream::parRun())
     {
         Info<< "\nWarning: not parallel - skipping further tests\n" << endl;
         return 0;
@@ -97,7 +97,7 @@ int main(int argc, char *argv[])
     DynamicList<MPI_Request> recvRequests(10);
 
 
-    if (!Pstream::master())
+    if (UPstream::is_subrank())
     {
         // Send some random length to master