Pipeline - Move Authenticator settings to the Pipeline Level. AGJS-74

This adds the ability to specify the authenticator settings on the pipeline level.

so:

    var authenticator = "authenticator instantiation goes here";

    var pipeline = AeroGear.Pipeline( { authenticator: authenticator } );


now all pipes that are created in that pipeline will have the same authenticator

If an authenticator is specified during pipe creation and there is a pipeline level one,  the pipeline one wins

added a @deprecated to the docs for the pipe setting