Steam Workshop for maps

[list] [*] Steam Workshop for maps: Upload, update, browse, download. This also allows you to use Steam as a private cloud storage for your maps by simply limiting the visibility of your published maps [*] Added a Steam achievement [*] Export of webp adjusted. An image with 10k x 10k resolution now has about 9MB instead of about 60MB [*] In the settings dialog it can be switched off that the movement speed of the camera by mouse depends on the zoom level [*] The direction of walls and palisades can now be reversed [*] Plot Tool for citizens [*] Small performance optimizations and other small things [/list]