redesign components; description/error text and nice arrows are still missing
header of df-component now follows resizing, changed arrow design, increased component offset, made tests durable for offset changes
modified border radius and color of preview, added text to component, first try of initialize - not working properly together with dragging
added minimizer again
fixed small design issue of component
fix too tall component content after minimizing
implement more promise arguments
adapt error style to new design; fix position of error text and disable events