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

cscore/src/main/native/cpp/PropertyImpl.h

@@ -6,11 +6,10 @@
 #define CSCORE_PROPERTYIMPL_H_
 
 #include <string>
+#include <string_view>
 #include <vector>
 
 #include <wpi/Signal.h>
-#include <wpi/StringRef.h>
-#include <wpi/Twine.h>
 
 #include "cscore_c.h"
 
@@ -20,17 +19,17 @@ namespace cs {
 class PropertyImpl {
  public:
   PropertyImpl() = default;
-  explicit PropertyImpl(const wpi::Twine& name_);
-  PropertyImpl(const wpi::Twine& name_, CS_PropertyKind kind_, int step_,
+  explicit PropertyImpl(std::string_view name_);
+  PropertyImpl(std::string_view name_, CS_PropertyKind kind_, int step_,
                int defaultValue_, int value_);
-  PropertyImpl(const wpi::Twine& name_, CS_PropertyKind kind_, int minimum_,
+  PropertyImpl(std::string_view name_, CS_PropertyKind kind_, int minimum_,
                int maximum_, int step_, int defaultValue_, int value_);
   virtual ~PropertyImpl() = default;
   PropertyImpl(const PropertyImpl& oth) = delete;
   PropertyImpl& operator=(const PropertyImpl& oth) = delete;
 
   void SetValue(int v);
-  void SetValue(const wpi::Twine& v);
+  void SetValue(std::string_view v);
   void SetDefaultValue(int v);
 
   std::string name;