Cleanup includes

Reorder a few includes, include "position.h" where it was previously missing
and apply include-what-you-use suggestions. Also make the order of the includes
consistent, in the following way:

1. Related header (for .cpp files)
2. A blank line
3. C/C++ headers
4. A blank line
5. All other header files

closes https://github.com/official-stockfish/Stockfish/pull/4763
fixes https://github.com/official-stockfish/Stockfish/issues/4707

No functional change

src/ucioption.cpp

@@ -18,16 +18,23 @@
 
 #include <algorithm>
 #include <cassert>
+#include <cctype>
+#include <cstddef>
+#include <iosfwd>
+#include <istream>
+#include <map>
 #include <ostream>
 #include <sstream>
+#include <string>
 
 #include "evaluate.h"
 #include "misc.h"
 #include "search.h"
+#include "syzygy/tbprobe.h"
 #include "thread.h"
 #include "tt.h"
+#include "types.h"
 #include "uci.h"
-#include "syzygy/tbprobe.h"
 
 using std::string;