Added auto-create directories and files

If any folders are missing (or the settings.cfg file) the server will
create them (and fill the settings.cfg with default values)

Changed all "fremove" to "file_remove", as it seems to be a lot more
reliable.

Changed sign load/save code to match that of other world entities.
Updated maps and fly filterscripts

Added additional admin checks to "fly.pwn".

Improved the object placement code a lot, removed all actual object
functions from the script and added a RemoveBuildingForPlayer parser to
the load code. These functions can now be placed inside the .map files.

Will add maps to the scriptfiles soon, once intellectual
property/copyrights are sorted with the original creators.