Merge pull request #810 from csmith/master

Fix height paragraph box height calculation

Author: Jugen

richtextfx/src/main/java/org/fxmisc/richtext/ParagraphBox.java

@@ -228,7 +228,7 @@ protected double computePrefWidth(double ignoredHeight) {
     @Override
     protected double computePrefHeight(double width) {
         Insets insets = getInsets();
-        double overhead = getGraphicPrefWidth() - insets.getLeft() - insets.getRight();
+        double overhead = getGraphicPrefWidth() + insets.getLeft() + insets.getRight();
         return text.prefHeight(width - overhead) + insets.getTop() + insets.getBottom();
     }