hghave: be more tolerant to rst2html output
On Windows, rst2html.bat calls rst2html.py, printing something like:
"rst2html.py (Docutils"
(notice the extra ".py")
#!/bin/sh
"$TESTDIR/hghave" fifo || exit 80
hg init
mkfifo p
hg serve --stdio < p &
P=$!
(echo lock; echo addchangegroup; sleep 5) > p &
Q=$!
sleep 3
kill -HUP $P
wait
echo .hg/* .hg/store/*