Add HTML elements to Item array

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Current behavior
I'm working on a web application that allows the users to drag and drop HTML elements(buttons, input text ...), I tried to add those HTML elements to the sourceNestedItems array expecting to have draggable elements, but unfortunatly when i run the page on the server are all treated like simple strings inside div directive

Expected behavior
Draggable HTML elements instead div items

Reproduction of the problem

What is the motivation / use case for changing the behavior?

Please tell us about your environment:
phpStorm

• ngx-charts version: x.x.x

• Angular version: 5

• Browser: [all | Chrome XX | Firefox XX | IE XX | Safari XX | Mobile Chrome XX | Android X.X Web Browser | iOS XX Safari | iOS XX UIWebView | iOS XX WKWebView ]

• Language: [all | TypeScript X.X | ES6/7 | ES5]