get rid of piForeach

apply some code analyzer recommendations
ICU flag now check if libicu exists
prepare for more accurate growth of containers (limited PoT, then constantly increase size)

libs/main/io_utils/pifiletransfer.cpp

@@ -53,7 +53,7 @@ bool PIFileTransfer::send(const PIString & file) {
 
 bool PIFileTransfer::send(const PIStringList & files) {
 	PIVector<PIFile::FileInfo> fil;
-	piForeachC(PIString & file, files)
+	for (const auto & file: files)
 		fil << PIFile::fileInfo(file);
 	return send(fil);
 }
@@ -305,7 +305,7 @@ void PIFileTransfer::receive_finished(bool ok) {
 			desc >> files_;
 			//			piCoutObj << files_;
 			PIStringList files;
-			piForeachC(PFTFileInfo & fi, files_)
+			for (const auto & fi: files_)
 				files << fi.dest_path;
 			pause();
 			receiveFilesRequest(files, bytesAll(), &user_ok);