Replace dying messages with messages in status

[fvieira]

Right now there are cases where the core changes to the ERROR state.
Since only the user can fix these cases, currently, the CLI is killing itself leaving a message in the configurations (not the best of places) which is shown on the next meocloud start.
A better way to handle this is to store the error message somewhere and just show it when the user calls meocloud status. This avoids storing messages in the configuration, and is clearer since the user will see the error as soon as he calls meocloud status instead of finding out that we died and seeing the message only at the next meocloud start.