Pluggable task id resolution

[grampelberg]

Currently, task id resolution is task id -> task id. For frameworks that use alternative ways to look up tasks, this makes it difficult to use the CLI.

So, the proposed solution is to add a configuration variable "task_id_resolution = []". This takes a list of python functions. The function will take a string and returns a list of task ids.

An example use case of this is marathon. You would be able to look up tasks based off marathon constraints (for example). If you had a constraint defined, instead of mesos tail task-id, you could now do mesos tail constraint.