Update flatc.cpp

Author: TGIshib

src/flatc.cpp

@@ -120,8 +120,9 @@ static void Error(const std::string &err, bool usage, bool show_exe_name) {
       "  --no-includes      Don\'t generate include statements for included\n"
       "                     schemas the generated file depends on (C++).\n"
       "  --gen-mutable      Generate accessors that can mutate buffers in-place.\n"
-      "  --gen-onefile      Generate single output file for C#\n"
-      "  --gen-name-strings Generate type name functions for C++.\n"
+      "  --gen-onefile      Generate single output file for C#.\n"
+      "  --gen-name-strings		 Generate type name functions for C++.\n"
+      "  --escape-proto-identifiers      Disable appending '_' in namespaces names.\n"
       "  --raw-binary       Allow binaries without file_indentifier to be read.\n"
       "                     This may crash flatc given a mismatched schema.\n"
       "  --proto            Input is a .proto, translate to .fbs.\n"