List.append is not flexible enought

List.append(text,label, id, onclick, user_data) allows to create a list item having the following form:

- if only text ist set: <li><a href='#'>$text</a></li>
- if text and label ist set: <li><a href='#'>text</a><label>$label</label></li>
- if text, label and id ist set: <li id="$id"><a href='#'>text</a><label>$label</label></li>

This method is however not flexible enought in practice. For example, it does not allow to add
- menu items with checkbox or switches
- menu items with image aside.
- menu items without right arrow ("i.e. withprogression")
- headers

Here are 3 suggestions that might be used instead

Alternativ 1:
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Declare a generic append method to add dom-element to a list:

list.append(domElement, onlick) // onclick is optional

In this case the developer has to create himself the elements (with document.createElement()).

Alternativ 2:
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Declare several utility methods to append element:

list.appendHeader(text,onclick)
list.appendCheckboxItem(text, asideImage, onclick) //asideImage and onclick are optionals
list.appendSwitchItem(text, asideImage, onclick) //asideImage and onclick are optionals
list.appendTextItem(text, asideImage, onclick, withproggression) //asideImage, onclick, withprogression are optionals. WithProgresson packs the text element in a <a> element, so that a link is displayed on the right side.
...
list.appendItem(domElement, onclick) // generic method, like in alternativ 1.

Alternative 3:
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Allow the declaration of list items in the list-prototype. The API could look like that:

var checkbox = List.checkboxItem('text', onclick);
var switch = List.switchItem('text', onclick);
var text = List.textItem('text', onclick);
var header = List.header('text',onclick);

list.append(header, checkbox, switch, text);