MFC r276527,r277648,r279154,r279397,r283584:

r276527:

Don't install h_raw if dealing with clang 3.5.0+ to unbreak the tests2 Jenkins
job

The h_raw application doesn't do proper bounds checking without the option
being supplied via the build, which means that it doesn't throw signals and
fail as expected

PR: 196430

r277648 (by jilles):

Enable utimensat tests from NetBSD.

As with other tests from c063, a required #include <sys/stat.h> was missing.

r279154 (by jilles):

nice(): Correct return value and [EPERM] error.

PR: 189821
Obtained from: NetBSD
Relnotes: yes

r279397 (by jilles):

nice(): Put back old return value, keeping [EPERM] error.

Commit r279154 changed the API and ABI significantly, and {NZERO} is still
wrong.

Also, preserve errno on success instead of setting it to 0.

PR: 189821
Relnotes: yes

r283584 (by emaste):

memmem(3): empty little string matches the beginning of the big string

This function originated in glibc, and this matches their behaviour
(and NetBSD, OpenBSD, and musl).

An empty big string (arg "l") is handled by the existing
l_len < s_len test.