The following are the subdirectories the I haven't included with the
reldist package:

src - The C, C++, or FORTRAN source files for the compiled code are
    in 'src', plus optionally file 'Makevars' or 'Makefile'.

demo - The 'demo' subdirectory is for R scripts (for running via 
     demo()) which demonstrate some of the functionality of the package.

inst - The contents of the 'inst' subdirectory will be copied 
     recursively to the installation directory.

tests - Subdirectory 'tests' is for additional package-specific 
      test code, similar to the specific tests that come with the 
      R distribution.