The shutdown hook is hooked into the JVM and is executed when the JVM stops.

This can be beneficial when the application is not managing pi4j's life cycle, but when an application wants to properly manage the life cycle, then this can be detrimental to the shutdown sequence of the application.

This change allows such an application to disable this feature.

The shutdown hook is still enabled by default, a future version might decide to disable it by default.

This removes the

    Pi4J.newAutoContextAllowMocks()

function, as we now detect these systems using:

    BoardInfoHelper.runningOnRaspberryPi()

This is a breaking API change, but should satisfy people having to write special code to load the mock in tests, as this happens automatically now.

If a mock is to be loaded on the Raspberry Pi, then one can still do this using the following code:

    Pi4J.newContextBuilder().autoDetectMockPlugins().build();