Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

mandoc complains loudly when <TAB>s are misused in columnated lists. Fix
this syntax violation and while I'm here also convert <TAB> to Ta and adjust
quotation marks in order to prevent this problem in the future.

mdoc: drop redundant .Pp and .LP calls

They have no effect when coming in pairs, or before .Bl/.Bd

Bump manual page timestamps.

Add NFSv4 ACL support to libc.

This adds the following functions to the acl(3) API: acl_add_flag_np,
acl_clear_flags_np, acl_create_entry_np, acl_delete_entry_np,
acl_delete_flag_np, acl_get_extended_np, acl_get_flag_np, acl_get_flagset_np,
acl_set_extended_np, acl_set_flagset_np, acl_to_text_np, acl_is_trivial_np,
acl_strip_np, acl_get_brand_np. Most of them are similar to what Darwin
does. There are no backward-incompatible changes.

Approved by: rwatson@

Improve API documentation.

Reviewed by: rwatson (earlier version)

Replace the non-standard disclaimer with the standard one from /COPYRIGHT

Approved by: jedgar@

mdoc(7) police: "The .Fn function".

mdoc(7) police: Use the new .In macro for #include statements.

Fix cross-references:
xntpd.8 --> ntpd.8
acl_delete_perms.3 --> acl_delete_perm.3
getname.2 --> getsockname.2

MFC after: 1 week

Record -lposix1e merge with -lc.

mdoc(7) police: fix markup.

Add the following ACL editing functions:
acl_add_perm, acl_clear_perms, acl_copy_entry, acl_create_entry,
acl_delete_perm, acl_get_permset, acl_get_qualifier, acl_get_tag_type,
acl_set_permset, acl_set_qualifier, acl_set_tag_type

This brings us within 4 functions of a full ACL editing library.

Reviewed by: rwatson