Better handle high-precision numbers in plotter

WebGL has relatively low floating point precision, and so attempting to
closely examine any signal which had even modest levels of precision
(e.g., attempting to plot a 32-bit integer) is an issue.

Add logic to pre-scale all of our points and readjust them periodically
while zooming to avoid precision issues.

Change-Id: Ibd51310fc2004a30c142bd5923a57961b6a20036
diff --git a/frc971/wpilib/BUILD b/frc971/wpilib/BUILD
index 087c413..00896bb 100644
--- a/frc971/wpilib/BUILD
+++ b/frc971/wpilib/BUILD
@@ -441,6 +441,7 @@
         ":imu_batch_ts_fbs",
         "//aos:configuration_ts_fbs",
         "//aos/network/www:aos_plotter",
+        "//aos/network/www:plotter",
         "//aos/network/www:reflection_ts",
         "@com_github_google_flatbuffers//ts:flatbuffers_ts",
     ],