Added ahal

This is a formatted copy of WPILib's default user-visible C++ API, with
a bit of completely unnecessary functionality stripped out. Most of the
stripping so far is only related to weird threading decisions.

Change-Id: Icbfd949b48cd115561862cb909bcc572aba0e753
diff --git a/frc971/wpilib/ahal/Servo.cc b/frc971/wpilib/ahal/Servo.cc
new file mode 100644
index 0000000..0cebf80
--- /dev/null
+++ b/frc971/wpilib/ahal/Servo.cc
@@ -0,0 +1,27 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2008-2017. 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 "frc971/wpilib/ahal/Servo.h"
+
+using namespace frc;
+
+constexpr double Servo::kDefaultMaxServoPWM;
+constexpr double Servo::kDefaultMinServoPWM;
+
+/**
+ * @param channel The PWM channel to which the servo is attached. 0-9 are
+ *                on-board, 10-19 are on the MXP port
+ */
+Servo::Servo(int channel) : PWM(channel) {
+  // Set minimum and maximum PWM values supported by the servo
+  SetBounds(kDefaultMaxServoPWM, 0.0, 0.0, 0.0, kDefaultMinServoPWM);
+
+  // Assign defaults for period multiplier for the servo PWM control signal
+  SetPeriodMultiplier(kPeriodMultiplier_4X);
+}
+
+Servo::~Servo() {}