RFR: JDK-8048710 Use ServiceLoader for the jvmstat protocols

[Staffan Larsen]

All,

The jvmstat implementation has three different protocols (file, local and rmi). These protocol implementations are currently loaded with Class.forName() using a specific scheme to create the class name. A more standard approach is to use ServiceLoader for this instead. This also makes it easier to break out different implementation classes for different packagings.

webrev: http://cr.openjdk.java.net/~sla/8048710/webrev.00/
bug: https://bugs.openjdk.java.net/browse/JDK-8048710

Thanks,
/Staffan