Please provide fmt::printf which writes to BasicArrayWriter

[sirzooro]

I would like to replace snprintf calls in my app with your lib. For performance reasons I do not want to use fmt::sprintf and then copy created string to its destination. Better approach would be to wrap memory buffer with BasicArrayWriter and write there. However at this moment fmt lib does not provide appropriate API for this. Please add it.

[vitaut]

Done in 6f8006c.

Now this should work:

fmt::MemoryWriter writer;
printf(writer, "%d", 42);

[sirzooro]

Thanks! I will give it a try tomorrow.