updated bundled fmt to contain printf

include/spdlog/fmt/bundled/printf.cc

+/*
+ Formatting library for C++
+
+ Copyright (c) 2012 - 2016, Victor Zverovich
+ All rights reserved.
+
+ For the license information refer to format.h.
+ */
+
+#include "format.h"
+#include "printf.h"
+
+namespace fmt {
+
+template <typename Char>
+void printf(BasicWriter<Char> &w, BasicCStringRef<Char> format, ArgList args);
+
+FMT_FUNC int fprintf(std::FILE *f, CStringRef format, ArgList args) {
+  MemoryWriter w;
+  printf(w, format, args);
+  std::size_t size = w.size();
+  return std::fwrite(w.data(), 1, size, f) < size ? -1 : static_cast<int>(size);
+}
+
+#ifndef FMT_HEADER_ONLY
+
+template void PrintfFormatter<char>::format(CStringRef format);
+template void PrintfFormatter<wchar_t>::format(WCStringRef format);
+
+#endif  // FMT_HEADER_ONLY
+
+}  // namespace fmt