Fix bug with bar plots having negative bars

Author: keller-mark

package.json

@@ -1,6 +1,6 @@
 {
   "name": "vueplotlib",
-  "version": "1.11.3",
+  "version": "1.11.4",
   "private": false,
   "scripts": {
     "serve": "vue-cli-service serve --open ./examples-src/index.js",

src/two.js

@@ -10,6 +10,11 @@ class TwoRectangle {
         this.width = width;
         this.height = height;
 
+        if(this.height < 0) {
+            // To fix bug with bar plots that have bars representing negative values.
+            this.height = this.height * -1;
+        }
+
         this.stroke = "#000";
         this.fill = "#000";
         this.linewidth = 1;