Simplify sub-classing `Master`, `Minion` and `Syndic` + PEP-8.

* Since we no longer suffer from too early logger initiation, replace any `logging.getLogger(__name__)` calls with an initial defined `logger`(not `log` so it does not clash with `salt.log`.
Comply with the convention and still provide the ability to subclass masters and minions.
The syndic also `start()`'s it does not `run()`.
Merge pull request #3253 from s0undt3ch/features/minion-subclass

Simplify sub-classing `Master`, `Minion` and `Syndic` + PEP-8.