Small change to allow plugins to read settings using $.summernote.allOptions

Example settings

$('.summernote').summernote({
        height: 200,
        tabsize: 2,
        lang: 'en-US',
        toolbar: [
  		    ['style', ['bold', 'italic', 'underline', 'clear']],
  		    ['color', ['color']],
  		    ['para', ['ul', 'ol', 'paragraph']],
  		    ['height', ['height']],
  		    ['table', ['table']],
  		    ['insert', ['video']]
  		  ],
        plugins: {
            hello: {
                foo: bar
            }
         }
}

In the plugin, this could be referred as below

var options = {};
    if ($.summernote.allOptions && $.summernote.allOptions.plugins && $.summernote.allOptions.plugins.hello) {
      foo = $.summernote.allOptions.plugins.hello.foo;
    }