Consistency cleanups for top-level Makefile:

- use the .install.* files under $(SRC) as already done with
  build-ok-file to avoid conflicts when using a shadow tree, i.e.
  .install.tmp -> $(SRC)/.apaci.install.tmp
  .install.conf -> $(SRC)/.apaci.install.conf

- use same tree copy variants for includes as already done for
  htdocs, etc.: CP -> $(TAR)+find, etc.

- show real source filenames (but with an "[*]" mark to indicate that the
  source is on-the-fly adjusted) instead of the unmeaningly filename of the
  temporary file.

- more parameter usage for commands:
  "ln" -> $(LN), "rm -f" -> $(RM)


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@81020 13f79535-47bb-0310-9956-ffa450edef68