Add customize menu

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/*
<javascriptresource>
<name>Convert background to layer(2)</name>
<menu>filter</menu>
<about>JavaScript Convert background to layer with</about>
<category>Layer</category>
<enableinfo>true</enableinfo>
</javascriptresource>
*/
// Convert background to layer
var ptr = app.activeDocument.layers.length;
app.activeDocument.layers[ptr - 1].isBackgroundLayer = false;