Renamed folders for consistency, using sim/athena/shared schema (#27)

Rename the following folders:
hal/lib/Athena -> hal/lib/athena
hal/lib/Desktop -> hal/lib/sim
hal/lib/Shared -> hal/lib/shared
wpilibc/Athena -> wpilibc/athena
wpilibc/simulation -> wpilibc/sim

Windows users may need to run gradlew clean after updating.

wpilibc/athena/src/SD540.cpp

@@ -0,0 +1,41 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2008-2016. All Rights Reserved.                        */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include "SD540.h"
+
+#include "LiveWindow/LiveWindow.h"
+
+/**
+ * Note that the SD540 uses the following bounds for PWM values. These values
+ * should work reasonably well for most controllers, but if users experience
+ * issues such as asymmetric behavior around the deadband or inability to
+ * saturate the controller in either direction, calibration is recommended.
+ * The calibration procedure can be found in the SD540 User Manual available
+ * from Mindsensors.
+ *
+ *   2.05ms = full "forward"
+ *   1.55ms = the "high end" of the deadband range
+ *   1.50ms = center of the deadband range (off)
+ *   1.44ms = the "low end" of the deadband range
+ *   0.94ms = full "reverse"
+ */
+
+/**
+ * Constructor for a SD540.
+ *
+ * @param channel The PWM channel that the SD540 is attached to. 0-9 are
+ *                on-board, 10-19 are on the MXP port
+ */
+SD540::SD540(uint32_t channel) : PWMSpeedController(channel) {
+  SetBounds(2.05, 1.55, 1.50, 1.44, .94);
+  SetPeriodMultiplier(kPeriodMultiplier_1X);
+  SetRaw(m_centerPwm);
+  SetZeroLatch();
+
+  HALReport(HALUsageReporting::kResourceType_MindsensorsSD540, GetChannel());
+  LiveWindow::GetInstance()->AddActuator("SD540", GetChannel(), this);
+}