Refactored pom.xml files to use `<pluginManagement>` tag correctly
Fixed FindBugs warning in ZoneMessage
Working on refactoring Server
Added assertion for logging in to server
Server now shuts down in a better way when using `exit` command
Moved `ClientIO` class and added tests for starting game
Added a test to play a game against AI Loser
Disabled Enchanting action for AI Medium
Added an export feature to export data from entities
Added sending of user status changes and requesting user statuses
Changed a unit test because the order of online users can be different
Merge branch 'client-server' of https://github.com/Cardshifter/Cardshifter into javafx