Update to the 2019 wpilib

Lots of gratuitious incompatibilities to deal with. Started sanifying a
few classes rather than figuring out how to update them too. Has not yet
been tested on a robot, but everything still builds so it should be
fine.

Also ported over our FPGA timestamp fixes, which were previously only in
allwpilib_2018.

Also upgraded to the new roborio compiler, which has to happen at the
same time due to incompatible pre-compiled libraries.

Change-Id: Ib9b6ad8fc0112d90a9855afe1b706588ef4ebde9
diff --git a/frc971/wpilib/ADIS16448.cc b/frc971/wpilib/ADIS16448.cc
index 6c4a6d1..21a5e2c 100644
--- a/frc971/wpilib/ADIS16448.cc
+++ b/frc971/wpilib/ADIS16448.cc
@@ -236,7 +236,10 @@
     }
 
     auto message = imu_values.MakeMessage();
-    message->fpga_timestamp = dio1_->ReadRisingTimestamp();
+    message->fpga_timestamp =
+        chrono::duration_cast<chrono::duration<double>>(
+            dio1_->ReadRisingTimestamp().time_since_epoch())
+            .count();
     message->monotonic_timestamp_ns =
         chrono::duration_cast<chrono::nanoseconds>(read_time.time_since_epoch())
             .count();