[Feature] detect new and stopped containers during runtime

[tsfoer]

Currently ofelia is only capable of detecting containers during startup. Stopped or destroyed containers are also not detected leading to errors like:

common.go:117 ▶ ERROR [Job "testjob" (4ffe34388a00)] Finished in "3.3764ms", failed: true, skipped: false, error: error creating exec: No such container: hopeful_gates

This could be fixed if ofelia would detect container starts and stops during its runtime which also would extend the overall utility of ofelia (maybe by polling the socket every X seconds or listening to events on the socket).

[rdelcorro]

I am using docker labels and ofelia reads it once and never again. If you change the command, modify the schedule, even remove the labels, it does not detect it. You have to restart ofelia, which is not great as it may be running some other job. Ideally jobs should be updated dynamically, the same way you add a task. Adding it on this feature request as I do also see the same behavior when I stop the container. The job is still being scheduled

[rdelcorro]

I have fixed this here: #137

[4n70w4]

similar: #78