Add Photonlib (#231)

Merges Photonlib into Photonvision, along with the Photonlib code examples. Also creates a new PhotonTargeting library teams can depend on.

photon-lib/src/main/native/cpp/photonlib/SimVisionTarget.cpp

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) Photon Vision.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "photonlib/SimVisionTarget.h"
+
+namespace photonlib {
+
+SimVisionTarget::SimVisionTarget(frc::Pose2d& targetPos,
+                                 units::meter_t targetHeightAboveGround,
+                                 units::meter_t targetWidth,
+                                 units::meter_t targetHeight)
+    : targetPos(targetPos),
+      targetHeightAboveGround(targetHeightAboveGround),
+      targetWidth(targetWidth),
+      targetHeight(targetHeight) {
+  tgtArea = targetWidth * targetHeight;
+}
+
+}  // namespace photonlib