Reintroduced copy error button.

Revert "Reverted 'copy error' button for 1.0.5, waiting for a better UI design"

This reverts commit cf4584e.

Author: cmaglie

app/src/processing/app/EditorStatus.java

@@ -125,7 +125,7 @@ public void unnotice(String unmessage) {
   public void error(String message) {
     mode = ERR;
     this.message = message;
-//    copyErrorButton.setVisible(true);
+    copyErrorButton.setVisible(true);
     repaint();
   }
 
@@ -196,7 +196,7 @@ public void progressIndeterminate(String message)
     progressBar.setIndeterminate(true);
     progressBar.setValue(50);
     progressBar.setVisible(true);
-//    copyErrorButton.setVisible(false);
+    copyErrorButton.setVisible(false);
     setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
     repaint();
   }