Returns true if this is a binary (zipped) module, and
false if it is expanded.
If true, members() should return only a single element -
the binary (jar or zip file) that contains the contents of
this module. (a single IModuleResource, e.g.
myejb.jar) Also, getLocation() should return the full path
up to and including the binary itself. (e.g.
c:\temp\myejb.jar)
If false, members() should return the entire contents
of the module, starting at the root. There should be no
preceeding directory structure. (an array of
IModuleResources, e.g. index.html, WEB-INF/web.xml,
...) In this case, getLocation() should return the path to
the root folder containing these resources.
