Respect server.properties

[fenhl]

Tracking issue for implementation of all server.properties fields.

• [ ] allow-flight
• [ ] allow-nether
• [ ] announce-player-achievements
• [ ] difficulty
• [ ] enable-query
• [ ] enable-rcon
• [ ] enable-command-block
• [ ] force-gamemode
• [ ] gamemode
• [ ] generate-structures
• [ ] generator-settings
• [ ] hardcore
• [ ] level-name
• [ ] level-seed
• [ ] level-type
• [ ] max-build-height
• [ ] max-players
• [ ] max-tick-time
• [ ] max-world-size
• [ ] motd
• [ ] network-compression-threshold
• [ ] online-mode
• [ ] op-permission-level
• [ ] player-idle-timeout
• [ ] pvp
• [ ] query.port
• [ ] rcon.password
• [ ] rcon.port
• [ ] resource-pack
• [ ] resource-pack-hash
• [x] server-ip (implemented in #40)
• [x] server-port (implemented in #40)
• [ ] snooper-enabled
• [ ] spawn-animals
• [ ] spawn-monsters
• [ ] spawn-npcs
• [ ] spawn-protection
• [ ] use-native-transport
• [ ] view-distance
• [ ] white-list