sshpeer: add implementation of _calltwowaystream
This implements the call needed by bundle2. The error handling is a bit flaky
right now, but bundle2 error handling in general is still flaky anyway. Bundle2
is still disabled by default, I do not expect this to be a problem.
Test document extraction
$ "$TESTDIR/hghave" docutils || exit 80
$ HGENCODING=UTF-8
$ export HGENCODING
$ { echo C; ls "$TESTDIR/../i18n"/*.po | sort; } | while read PO; do
> LOCALE=`basename "$PO" .po`
> echo
> echo "% extracting documentation from $LOCALE"
> echo ".. -*- coding: utf-8 -*-" > gendoc-$LOCALE.txt
> echo "" >> gendoc-$LOCALE.txt
> LANGUAGE=$LOCALE python "$TESTDIR/../doc/gendoc.py" >> gendoc-$LOCALE.txt 2> /dev/null || exit
>
> if [ $LOCALE != C ]; then
> cmp -s gendoc-C.txt gendoc-$LOCALE.txt && echo '** NOTHING TRANSLATED **'
> fi
>
> # We call runrst without adding "--halt warning" to make it report
> # all errors instead of stopping on the first one.
> echo "checking for parse errors"
> python "$TESTDIR/../doc/runrst" html gendoc-$LOCALE.txt /dev/null
> done
% extracting documentation from C
checking for parse errors
% extracting documentation from da
checking for parse errors
% extracting documentation from de
checking for parse errors
% extracting documentation from el
checking for parse errors
% extracting documentation from fr
checking for parse errors
% extracting documentation from it
checking for parse errors
% extracting documentation from ja
checking for parse errors
% extracting documentation from pt_BR
checking for parse errors
% extracting documentation from ro
checking for parse errors
% extracting documentation from ru
checking for parse errors
% extracting documentation from sv
checking for parse errors
% extracting documentation from zh_CN
checking for parse errors
% extracting documentation from zh_TW
checking for parse errors