Use std::string_view and fmtlib across all libraries (#3402)

- Twine, StringRef, Format, and NativeFormatting have been removed
- Logging now uses fmtlib style formatting
- Nearly all uses of wpi::outs/errs have been replaced with fmt::print() or
std::puts()/std::fputs() (for unformatted strings).
- A wpi/fmt/raw_ostream.h header has been added to enable
fmt::print() with wpi::raw_ostream

simulation/halsim_ws_server/src/main/native/cpp/main.cpp

@@ -2,10 +2,10 @@
 // Open Source Software; you can modify and/or share it under the terms of
 // the WPILib BSD license file in the root directory of this project.
 
+#include <cstdio>
 #include <memory>
 
 #include <hal/Extensions.h>
-#include <wpi/raw_ostream.h>
 
 #include "HALSimWSServer.h"
 
@@ -19,7 +19,7 @@ extern "C" {
 __declspec(dllexport)
 #endif
     int HALSIM_InitExtension(void) {
-  wpi::outs() << "Websocket WS Server Initializing.\n";
+  std::puts("Websocket WS Server Initializing.");
 
   HAL_OnShutdown(nullptr, [](void*) { gServer.reset(); });
 
@@ -28,7 +28,7 @@ __declspec(dllexport)
     return -1;
   }
 
-  wpi::outs() << "Websocket WS Server Initialized!\n";
+  std::puts("Websocket WS Server Initialized!");
   return 0;
 }
 }  // extern "C"