minor code format fix in rpc-related files

src/rpcmisc.cpp

@@ -22,10 +22,10 @@
 #include "json/json_spirit_utils.h"
 #include "json/json_spirit_value.h"
 
-using namespace std;
 using namespace boost;
 using namespace boost::assign;
 using namespace json_spirit;
+using namespace std;
 
 Value getinfo(const Array& params, bool fHelp)
 {