Add "Asset maps" section to the menu

Similar to "search filter for asset maps in Explore page" suggestion, now with the ability of copy and pasting, the asset maps could take over the Explore page making it hard to look for actual maps, adding an Extra page for them next to "maps, Art Manager, Explore, My Feed" might be a better idea. Additionally The asset maps could be used as group stamps, automatically being copy and pasted as a group when used.