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/smartdashboard/Mechanism2d.h

@@ -59,7 +59,7 @@ class Mechanism2d : public Sendable, public SendableHelper<Mechanism2d> {
    * @param y the root y coordinate
    * @return a new root object, or the existing one with the given name.
    */
-  MechanismRoot2d* GetRoot(wpi::StringRef name, double x, double y);
+  MechanismRoot2d* GetRoot(std::string_view name, double x, double y);
 
   /**
    * Set the Mechanism2d background color.