Proposal: #ResourceExistenceAndSize

[mark.reinhold at oracle.com]

Issue summary
-------------

  #ResourceExistenceAndSize -- Given a `Module` object and a resource
  name, should there be a way to determine whether that resource exists
  in that module and, if it does exist, what its size is, without
  actually opening the resource as a stream?  One way to do this would be
  to introduce a new abstraction to represent resources.  [1]

Proposal
--------

This could be a useful feature, but it is not required for the initial
release and could be added in a later revision.


[1] http://openjdk.java.net/projects/jigsaw/spec/issues/#ResourceExistenceAndSize