Reinstall a clean drupal 8 site

d8_reset.sh

#!/bin/sh

# Removes an existing Drupal 8 install, then install again.
# Requires Drush 7 - https://github.com/drush-ops/drush
#
# Run this script from the docroot of a Drupal 8 checkout.
# Installs to mysql://localhost/drupal, user 1 user/pass is admin/admin.

if [ ! -e ./core/core.services.yml ]
then
  echo "You need to run this script from the root of a Drupal 8 install."
  exit
fi

# MySQL
echo "Dropping and recreating 'drupal' database.\n"
mysql -u user -ppass -e "drop database drupal"
mysql -u user -ppass -e "create database drupal"


echo "Removing files created during drupal install. You will be asked for your password, for sudo.\n"
rm -f ./sites/default/settings.php
rm -rf ./sites/simpletest
cp ./sites/default/default.settings.php ./sites/default/settings.php
rm -rf ./sites/default/files
mkdir ./sites/default/files

chmod 777 -R ./sites/default

# Now install a Drupal.
# Minimal install
#drush si minimal --account-name=admin --account-pass=admin --db-url=mysql://user:pass@localhost/drupal -yv

# Standard install
drush si  --account-name=admin --account-pass=admin --db-url=mysql://user:pass@localhost/drupal -yv
drush cr

Some commands might need sudo adding to them for permission-y stuff