execsnoop: use strftime instead of elapsed

[makelinux]

because elapsed gives relative time, and strftime gives absolute time which is more readable and practical.

[viktormalik]

Makes sense to me. Maybe we could just respect the original implementation and use ms instead of ns?

[makelinux]

Makes sense to me. Maybe we could just respect the original implementation and use ms instead of ns?

strftime receives integer nanoseconds and provides decimal seconds only in microseconds (six digits). It can't be changed.

[danobi]

seems reasonable to me. but please add changelog entry under "tools" section

[viktormalik]

Makes sense to me. Maybe we could just respect the original implementation and use ms instead of ns?

strftime receives integer nanoseconds and provides decimal seconds only in microseconds (six digits). It can't be changed.

Right, that makes sense. Ok, let's stick with us.