tools: add small donate button in the statusbar

tools/level_editor/resources/resources.gresource.xml

@@ -148,6 +148,7 @@
     <file compressed="true" preprocess="xml-stripblanks">icons/crown.svg</file>
     <file compressed="true" preprocess="xml-stripblanks">icons/game-run-symbolic.svg</file>
     <file compressed="true" preprocess="xml-stripblanks">icons/game-stop-symbolic.svg</file>
+    <file compressed="true" preprocess="xml-stripblanks">icons/hearth-symbolic.svg</file>
     <file compressed="true" preprocess="xml-stripblanks">icons/layer-locked-symbolic.svg</file>
     <file compressed="true" preprocess="xml-stripblanks">icons/layer-visible-symbolic.svg</file>
     <file compressed="true" preprocess="xml-stripblanks">icons/level-layers-symbolic.svg</file>

tools/level_editor/statusbar.vala

@@ -15,6 +15,7 @@ public class Statusbar : Gtk.Box
 	// Widgets
 	public Gtk.Label _status;
 	public Gtk.Label _temporary_message;
+	public Gtk.Button _donate;
 	public Gtk.Button _version;
 
 	public Statusbar()
@@ -29,6 +30,11 @@ public class Statusbar : Gtk.Box
 		// Widgets
 		_status = new Gtk.Label("Idle");
 		_temporary_message = new Gtk.Label("");
+		_donate = new Gtk.Button.from_icon_name("hearth-symbolic", Gtk.IconSize.SMALL_TOOLBAR);
+		_donate.get_style_context().add_class("flat");
+		_donate.clicked.connect(() => {
+				GLib.Application.get_default().activate_action("donate", null);
+			});
 		_version = new Gtk.Button.with_label(CROWN_VERSION);
 		_version.get_style_context().add_class("flat");
 		_version.get_style_context().add_class("compact");
@@ -39,6 +45,7 @@ public class Statusbar : Gtk.Box
 		this.pack_start(_status, false, false, 0);
 		this.pack_start(_temporary_message, false, false, 0);
 		this.pack_end(_version, false, false, 0);
+		this.pack_end(_donate, false, false, 6);
 		this.get_style_context().add_class("statusbar");
 	}