Make it possible to plot all the nodes in timestamp_plot

It is quite handy to debug the solver with all the data visible.  Add a
--all flag to support that.

Change-Id: Iba8dd3bdb4c2397afb9e774aa138b8f932e99dda
Signed-off-by: Austin Schuh <austin.schuh@bluerivertech.com>
diff --git a/frc971/analysis/in_process_plotter.h b/frc971/analysis/in_process_plotter.h
index b78a8fb..4f05c19 100644
--- a/frc971/analysis/in_process_plotter.h
+++ b/frc971/analysis/in_process_plotter.h
@@ -46,6 +46,7 @@
     std::string_view label = "";
     std::string_view line_style = "*-";
     std::string_view color = "";
+    double point_size = 3.0;
   };
 
   void AddLine(const std::vector<double> &x, const std::vector<double> &y,