Couple of tweaks from Ingo Schwartze:
  * Correct the license description;
  * Install copyright and source package to satisfy the license;
  * Use shorter path for actual files: apropos won't be very useful
    since this packages relies on man(7) markup instead of mdoc(7);
  * Small README and DESCR tweaks.
Remove books/man-pages-posix, imported to CVS.