Fixes missing function for Timer::GetMatchTime() (#299)

wpilibc/athena/src/Timer.cpp

@@ -11,6 +11,7 @@
 #include <iostream>
 #include <thread>
 
+#include "DriverStation.h"
 #include "HAL/HAL.h"
 #include "Utility.h"
 
@@ -165,3 +166,20 @@ double Timer::GetFPGATimestamp() {
   // Call the helper GetFPGATime() in Utility.cpp
   return GetFPGATime() * 1.0e-6;
 }
+
+/**
+ * Return the approximate match time The FMS does not currently send the
+ * official match time to
+ * the robots This returns the time since the enable signal sent from the Driver
+ * Station At the
+ * beginning of autonomous, the time is reset to 0.0 seconds At the beginning of
+ * teleop, the time
+ * is reset to +15.0 seconds If the robot is disabled, this returns 0.0 seconds
+ * Warning: This is
+ * not an official time (so it cannot be used to argue with referees).
+ *
+ * @return Match time in seconds since the beginning of autonomous
+ */
+double Timer::GetMatchTime() {
+  return DriverStation::GetInstance().GetMatchTime();
+}