The server will save the map to a file named "map" in the directory it is run in. It will also load the map from there at startup, given that the file exists.
-## Nodes:
-- `unloaded`: used for nodes in unloaded mapblocks
-- `air`: default node in newly generated mapblocks
-- `dirt`
-- `grass`
-- `stone`
-- `invalid`: unknown nodes received from server
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Interrupt handlers for SIGINT und SIGTERM are implemented.