Adding new file types to the build process
  Sometimes you might have extra types of files that you want to install
  alongside the standard types like .pm and .pod files. For instance, you
  might have a Bar.dat file containing some data related to the "Foo::Bar"
  module. Assuming the data doesn't need to be created on the fly, the
  best place for it to end up is probably as Foo/Bar.dat somewhere in
  perl's @INC path so "Foo::Bar" can access it easily at runtime. The
  following code from a sample "Build.PL" file demonstrates how to
  accomplish this: