[wpilib] Add AprilTag and AprilTagFieldLayout (#4421)

This is an API for looking up a Pose3d from a tag id, and includes functionality to load that map from a JSON file.

This also adds JSON support to Pose3d, Rotation3d. Translation3d, and Quaternion.

Co-authored-by: Tyler Veness <calcmogul@gmail.com>
Co-authored-by: AMereBagatelle <themerebagatelle@gmail.com>

wpimath/src/main/native/include/frc/geometry/Pose3d.h

@@ -11,6 +11,10 @@
 #include "Translation3d.h"
 #include "Twist3d.h"
 
+namespace wpi {
+class json;
+}  // namespace wpi
+
 namespace frc {
 
 /**
@@ -202,4 +206,10 @@ class WPILIB_DLLEXPORT Pose3d {
   Rotation3d m_rotation;
 };
 
+WPILIB_DLLEXPORT
+void to_json(wpi::json& json, const Pose3d& pose);
+
+WPILIB_DLLEXPORT
+void from_json(const wpi::json& json, Pose3d& pose);
+
 }  // namespace frc