message: Remove default block size
diff: @@ -476,7 +476,7 @@ public:
  class BlockILU0 : public Solver
  {
  public:
  - BlockILU0(int block_size_ = 1, bool reorder_ = true);
  + BlockILU0(int block_size_, bool reorder_ = true);
  BlockILU0(Operator &op, int block_size_ = 1, bool reorder_ = true);
  