Print "unknown" to stdout when unix-time-to-fmt.py was called without
an argument, instead of printing a Python stack trace to stderr. It gets
called that way when building outside of a git folder.
Change-Id: I3ba27cc23543e47cc8a1e494c35cc33f1dc8f297
On FreeBSD, the 'date' command's -d option has a completely different meaning.
Instead, use a small python script to do the date format conversion, which
should be more portable.
As a side effect, we now also use UTC instead of the build server's timezone,
which may be considered a more international choice.
Add build/unix-time-to-fmt.py, call in build/Makefile.asciidoc.inc.
Change-Id: I91a40656184f553ee375216d8ba5c7788fe9990d
Oliver Smith
Neels Hofmeyr