ExecutorScheduler unspecified API

```
public final class ExecutorScheduler
extends Scheduler
                    
```
Scheduler that wraps an Executor instance and establishes the Scheduler contract upon it.
Note that thread-hopping is unavoidable with this kind of Scheduler as we don't know about the underlying threading behavior of the executor.

Constructor Summary

Constructors
Constructor	Description
`ExecutorScheduler(Executor executor)`

Method Summary

Modifier and Type	Method	Description
`Scheduler.Worker`	`createWorker()`	Retrieves or creates a new Scheduler.Worker that represents serial execution of actions.

Methods inherited from class com.tds.common.reactor.schedulers.Scheduler
now
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - ExecutorScheduler
```
ExecutorScheduler(Executor executor)
```
- Method Detail
  - createWorker
```
 Scheduler.Worker createWorker()
```
    Retrieves or creates a new Scheduler.Worker that represents serial execution of actions.
    When work is completed it should be unsubscribed using unsubscribe.
    Work on a Scheduler.Worker is guaranteed to be sequential.