Update the temporary original placeholder files only if they aren't currently correct, rather than updating them every time.  Some machines may never get a given file, in which case we spit out a message to the user and update the placeholder every time etch runs, which quickly gets annoying.
Update the temporary original placeholder files only if they aren't
currently correct, rather than updating them every time.  Some machines
may never get a given file, in which case we spit out a message to the
user and update the placeholder every time etch runs, which quickly gets
annoying.

Reverse the return value of compare_file_contents, compare_permissions 
and compare_ownership so that it makes more sense, and clean up the
code.  compare_link_destination was flipped a while back for the same 
reason.


git-svn-id: 907a5e332d9df9b9d6ff346e9993373f8c03b4a0@138 59d7d9da-0ff4-4beb-9ab8-e480f87378b2

Telmo/etch,Telmo/etch,Telmo/etch,Telmo/etch