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

wpilibc/src/main/native/include/frc/shuffleboard/Shuffleboard.h

@@ -4,7 +4,7 @@
 
 #pragma once
 
-#include <wpi/StringRef.h>
+#include <string_view>
 
 #include "frc/shuffleboard/RecordingController.h"
 #include "frc/shuffleboard/ShuffleboardEventImportance.h"
@@ -77,7 +77,7 @@ class Shuffleboard final {
    * @param title the title of the tab
    * @return the tab with the given title
    */
-  static ShuffleboardTab& GetTab(wpi::StringRef title);
+  static ShuffleboardTab& GetTab(std::string_view title);
 
   /**
    * Selects the tab in the dashboard with the given index in the range
@@ -93,7 +93,7 @@ class Shuffleboard final {
    *
    * @param title the title of the tab to select
    */
-  static void SelectTab(wpi::StringRef title);
+  static void SelectTab(std::string_view title);
 
   /**
    * Enables user control of widgets containing actuators: speed controllers,
@@ -141,7 +141,7 @@ class Shuffleboard final {
    *
    * @param format the format for the
    */
-  static void SetRecordingFileNameFormat(wpi::StringRef format);
+  static void SetRecordingFileNameFormat(std::string_view format);
 
   /**
    * Clears the custom name format for recording files. New recordings will use
@@ -163,7 +163,8 @@ class Shuffleboard final {
    * @param description a description of the event
    * @param importance  the importance of the event
    */
-  static void AddEventMarker(wpi::StringRef name, wpi::StringRef description,
+  static void AddEventMarker(std::string_view name,
+                             std::string_view description,
                              ShuffleboardEventImportance importance);
 
   /**
@@ -177,7 +178,7 @@ class Shuffleboard final {
    * @param name        the name of the event
    * @param importance  the importance of the event
    */
-  static void AddEventMarker(wpi::StringRef name,
+  static void AddEventMarker(std::string_view name,
                              ShuffleboardEventImportance importance);
 
  private: