Add NT controlled framerate limiter (#2257)

Adds a method to lower the speed of a pipeline over NT, primarily to
reduce power consumption.

photon-lib/src/main/native/include/photon/PhotonCamera.h

@@ -103,6 +103,16 @@ class PhotonCamera {
    */
   bool GetDriverMode() const;
 
+  /**
+   * @param fpsLimit The FPS limit to set. Use -1 for unlimited FPS.
+   */
+  void SetFPSLimit(int fpsLimit);
+
+  /**
+   * @return The FPS limit set on the camera, or -1 if no limit is set.
+   */
+  int GetFPSLimit() const;
+
   /**
    * Request the camera to save a new image file from the input
    * camera stream with overlays.
@@ -210,6 +220,9 @@ class PhotonCamera {
 
   nt::BooleanSubscriber driverModeSubscriber;
   nt::BooleanPublisher driverModePublisher;
+  nt::IntegerSubscriber fpsLimitSubscriber;
+  nt::IntegerPublisher fpsLimitPublisher;
+
   nt::IntegerSubscriber ledModeSubscriber;
 
   nt::IntegerSubscriber heartbeatSubscriber;