Add font size theme support & improve theme system

Filtration.ObjectModel/ThemeEditor/IntegerThemeComponent.cs

@@ -0,0 +1,35 @@
+using System;
+using System.Windows.Media;
+using Filtration.ObjectModel.Enums;
+
+namespace Filtration.ObjectModel.ThemeEditor
+{
+    [Serializable]
+    public class IntegerThemeComponent : ThemeComponent
+    {
+        private int _value;
+
+        public IntegerThemeComponent(ThemeComponentType componentType, string componentName, int componentValue)
+        {
+            if (componentName == null)
+            {
+                throw new ArgumentException("Null parameters not allowed in IntegerThemeComponent constructor");
+            }
+
+            ComponentType = componentType;
+            Value = componentValue;
+            ComponentName = componentName;
+        }
+
+        public int Value
+        {
+            get { return _value; }
+            set
+            {
+                _value = value;
+                OnPropertyChanged();
+                _themeComponentUpdatedEventHandler?.Invoke(this, EventArgs.Empty);
+            }
+        }
+    }
+}