sparse: clean up updateconfig()
* Use context manager for wlock
* Rename oldsparsematch to oldmatcher
* Always call parseconfig() because parsing an empty string yields
the same result as the old code
#!/bin/sh
# This scripts is used to install dependencies for
# testing Mercurial. Mainly used by Vagrant (see
# Vagrantfile for details).
export DEBIAN_FRONTEND=noninteractive
apt-get update
apt-get install -y -q python-dev unzip
# run-tests.sh is added by Vagrantfile
chmod +x run-tests.sh