Change the css in templatehints

1. we need to be able to click on an element in the template hints, open a popup with a textfield for the color (with a colorpickerr), textfield for fontsize and a save button to store the css in the database. The css should only apply to the specific template 2. make the blocks in the template hints draggable and store the additional xml in a database. When visiting the page the layout of the blocks in the database should override the xml