Edited the buildContextMenuHTML, so it does work even if the map element is nested inside many relative/absolute positioned elements
Made identation right
Unfortunately getBoundingClientRect() function introduced errors when scrolling down and when the map is only partly to see. So the function to find the absolute positioning of elements has to be introduced.
Merge pull request #170 from JustGoscha/master

Fixed ContentMenu positioning inside many nested relative/absolute elements