added custom-stylesheet script

custom-stylesheet/custom-stylesheet.qml

@@ -0,0 +1,33 @@
+import QtQml 2.0
+
+/**
+ * This script adds custom styles to the application
+ * 
+ * You can get the object names from the *.ui files, for example
+ * https://github.com/pbek/QOwnNotes/blob/develop/src/mainwindow.ui
+ * 
+ * Take a look at http://doc.qt.io/qt-5/stylesheet-reference.html for
+ * a reference of what styles are available.
+ */
+QtObject {
+    property string customStylesheet;
+
+    // register your settings variables so the user can set them in the script settings
+    property variant settingsVariables: [
+        {
+            "identifier": "customStylesheet",
+            "name": "Custom stylesheet",
+            "description": "Please enter your custom stylesheet:",
+            "type": "text",
+            "default": "QTreeWidget#noteTreeWidget {font-family: Pacifico; font-size: 28px;}",
+        },
+    ];
+
+    /**
+     * Adds custom styles
+     */
+    function init() {
+        // add a custom stylesheet to increase font size in the note list and set a font
+        script.addStyleSheet(customStylesheet);
+    }
+}

custom-stylesheet/info.json

@@ -0,0 +1,9 @@
+{
+  "name": "Custom user interface styles",
+  "identifier": "custom-stylesheet",
+  "script": "custom-stylesheet.qml",
+  "authors": ["@pbek"],
+  "version": "0.0.1",
+  "minAppVersion": "17.05.7",
+  "description" : "With this script you can add custom styles to the application. Please take a look at <a href='http://docs.qownnotes.org/en/develop/scripting/README.html#add-a-custom-stylesheet'>Add a custom stylesheet</a> to find out how to style QOwnNotes."
+}