Render the B/E fields in a way that's a little more insightful

src/render.rs

@@ -4,14 +4,14 @@ pub struct NumericTermRenderer;
 
 impl NumericTermRenderer {
     pub fn render(&self, state: &SimState) {
-        print!("E:");
-        for cell in state.cells() {
-            print!("{:>10.1e} ", cell.ez());
-        }
-        print!("\nB:      ");
+        print!("B:      ");
         for cell in state.cells() {
             print!("{:>10.1e} ", cell.by());
         }
+        print!("\nE:");
+        for cell in state.cells() {
+            print!("{:>10.1e} ", cell.ez());
+        }
         print!("\n");
     }
 }