Add ability to change the state of a component while its running

[symbiont-stevan-andjelkovic]

Currently we always initialise new components to some "initial state" when we spin them up. It would be nice to be able to "load" the end state from a previous test run in order to be able to pick up and continue testing from where we left off. It would also be nice to be able to "patch" the state of a running component to do hotfixes or simulate byzantine faults.

Note that something special would have to be done with the Init() messages if a test is resumed.