tests: remove utee

POSIX already stipulates tee(1) must be unbuffered.  I think my
decision to use utee was due to my being misled by a bug in
older curl where -N did not work as advertised (but --no-buffer
did).

N.B. we don't use tee in unicorn tests, this just matches
commit cbff7b0892148b037581541184364e0e91d2a138 in rainbows
tests: replace non-portable "date +%s" with ruby equivalent

"date +%s" is not in POSIX (it is in GNU, and at least FreeBSD
9.0, possibly earlier).  The Ruby equivalent should be
sufficiently portable between different Ruby versions.

This change was automated via:
    perl -i -p -e 's/date \+%s/unix_time/' t/*.sh

This is commit 0ba6fc3c30b9cf530faf7fcf5ce7be519ec13fe7
in rainbows.git
tests: "wc -c" portability for *BSDs

On FreeBSD 9.0, "wc -c" emits leading whitespace, so
filter it through tr -d '[:space:]' to eliminate it.

This is commit 8a6117a22a7d01eeb5adc63d3152acf435cd3176
in rainbows.git
tests: "wc -l" portability for *BSDs

On FreeBSD 9.0, "wc -l" emits leading whitespace, so
filter it through tr -d '[:space:]' to eliminate it.