change std::stringstream to std::ostringstream

src/misc.cpp

@@ -40,7 +40,7 @@ int StrToInt(std::string str)
 
 std::string IntoStr(int l)
 {
-	std::stringstream ss;
+	std::ostringstream ss;
 	ss << l;
 	return ss.str();
 }

src/song.cpp

@@ -540,7 +540,7 @@ bool Song::operator<(const Song &s) const
 
 string Song::ShowTime(int length)
 {
-	std::stringstream ss;
+	std::ostringstream ss;
 	
 	int hours = length/3600;
 	length -= hours*3600;

src/tag_editor.cpp

@@ -116,7 +116,7 @@ namespace
 
 	string ParseFilename(Song &s, string mask, bool preview)
 	{
-		std::stringstream result;
+		std::ostringstream result;
 		vector<string> separators;
 		vector< std::pair<char, string> > tags;
 		string file = s.GetName().substr(0, s.GetName().rfind("."));