[OPEN-1324] Error in CompositeField's documentation

[devnullable]

Documentation for CompositeField has misleading code in very first example. labelWidth is not a config option of CompositeField and therefore does not change width of labels.

{
    xtype: 'compositefield',
    labelWidth: 120
    items: [
        {
            xtype     : 'textfield',
            fieldLabel: 'Title',
            width     : 20
        },
        {
            xtype     : 'textfield',
            fieldLabel: 'First',
            flex      : 1
        },
        {
            xtype     : 'textfield',
            fieldLabel: 'Last',
            flex      : 1
        }
    ]
}