Partial merge with recent revisions from FreeBSD:

Partial merge with recent revisions from FreeBSD:

- pass -1 to setfile() (cp.c:1.49)
- When -R is not specified, fail to copy the contents of dangling
  symlinks instead of making a copy of the link itself, as required
  by SUSv3 (cp.c:1.36)
- Fix the case of a trailing slash following the destination
  mistakenly creating a file instead of a directory (cp.c:1.34)
- Mechanically kill hard sentence breaks in manual page (cp.1:1.29)
- Clarify what -p option does and spell "set-{user,group}-ID" with
  hyphens (cp.1:1.27)

Submitted-by: Sarunas Vancevicius <svan_at_redbrick_dot_dcu_dot_ie>