Public utilities classses

[Sergey Evdokimov <se...@gridgain.com>]

Hello,

I would like to propose to make GridNodePredicate public, because user need
to use it to configure cache. At least this class is needed for
ComputeClientPortableTaskExecutionExample
to configure this example to work on local node only.

Also methods like GridFunc#nodeForNodeId() should be moved to GridNodePredicate
class.

Also I think we should create public class "Predicates" that groups static
methods to work with IgnitePredicate. Now those methods located in GridFunc
and others private utilities classes.