add 'console.head_padding' option

app/src/processing/app/ui/Editor.java

@@ -2293,8 +2293,22 @@ public abstract class Editor extends JFrame implements RunnerListener {
     internalCloseRunner();
     statusEmpty();
 
-    // do this to advance/clear the terminal window / dos prompt / etc
-    for (int i = 0; i < 10; i++) System.out.println();
+    int headPadding;
+
+    try {
+      headPadding = Preferences.getInteger("console.head_padding");
+    } catch (NullPointerException e) {
+      // We need to handle this exception to take care of old versions of
+      // preference files, i.e., "defaults.txt" and "preferences.txt" which
+      // may not have the attribute 'console.head_padding'.
+      headPadding = 10;
+    }
+
+    // Do this to advance/clear the terminal window / dos prompt / etc.
+    // This may be useful especially when 'console.auto_clear' is false.
+    // TODO: use `console.message()` instead of `System.out.println()`?
+    // i.e. for (int i = 0; i < headPadding; i++) console.message("\n", false);
+    for (int i = 0; i < headPadding; i++) System.out.println();
 
     // clear the console on each run, unless the user doesn't want to
     if (Preferences.getBoolean("console.auto_clear")) {

build/shared/lib/defaults.txt

@@ -165,8 +165,16 @@ console.font.size = 12
 # number of lines to show by default
 console.lines = 4
 
-# set to false to disable automatically clearing the console
+# Number of blank lines to advance/clear console.
+# Note that those lines are also printed in the terminal when
+# Processing is executed there.
+# Setting to 0 stops this behavior.
+console.head_padding = 10
+
+# Set to false to disable automatically clearing the console
 # each time 'run' is hit
+# If one sets it to false, one may also want to set 'console.head_padding'
+# to a positive number to separate outputs from different runs.
 console.auto_clear = true
 
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