Crash with invalid config files

[rm-code]

The program crashes when the user has a corrupted config file:

Error: src/conf/ConfigReader.lua:82: attempt to index local 'value' (a nil value)
stack traceback:
    src/conf/ConfigReader.lua:82: in function 'loadFile'
    src/conf/ConfigReader.lua:138: in function 'init'
    src/screens/SelectionScreen.lua:83: in function 'init'
    lib/screenmanager/ScreenManager.lua:103: in function 'push'
    lib/screenmanager/ScreenManager.lua:63: in function 'init'
    main.lua:98: in function 'load'
    [string "boot.lua"]:418: in function <[string "boot.lua"]:413>
    [C]: in function 'xpcall'