serve: respect settings from .hg/hgrc
create_server was looking only at the root ui object, ignoring any
settings from .hg/hgrc. To keep respecting command-line arguments,
commands.serve must also call repo.ui.setconfig.
#!/bin/sh
# a test for issue586
hg init a
cd a
echo a > a
hg ci -Ama
hg init ../b
cd ../b
echo b > b
hg ci -Amb
hg pull -f ../a
hg merge
hg rm -f a
hg ci -Amc
hg st -A