Add versioning to perf SQL database

perf/db/reset_mysqldb.sh

+#!/bin/bash
+
+# NOTE: Intended for development and testing only. In production execute the
+# statements by hand.
+
+# Utility script to create or update the database.
+
+# get the command line arguments
+MYSQL_PW=$1
+MYSQL_RO_PW=$2
+MYSQL_RW_PW=$3
+
+if [[ -z $MYSQL_PW  ||  -z $MYSQL_RO_PW  ||  -z $MYSQL_RW_PW ]]
+        then
+        echo "Usage: $0 root_password readonly_password readwrite_password"
+        exit 1
+fi
+
+# Creat the database. Get the password for root from MYSQL_PW env variable.
+mysql -h localhost -u root -p$MYSQL_PW mysql <<EOF
+
+# uncomment to drop the database

[tfarina, 2014/09/29 18:55:27]

this comment says "uncomment", but the following line is already uncommented.
typo?

+DROP DATABASE IF EXISTS skia;

[jcgregorio, 2014/09/29 16:59:07]

This terrifies me. Can we just have the commands to add users and create
database? I'd rather have the DROP commands appear in a document that you have
to cut and paste as a hurdle to actually deleting our entire db.

[stephana, 2014/09/29 18:07:50]

That's why I have the note on top about this being for development and testing
only and the hostname is hardcoded into it. 
But I am fine with removing the whole file and keep the SQL statements in the
documentation.

[jcgregorio, 2014/09/29 20:19:09]

Thanks, let's keep the SQL statements in the docs.

[stephana, 2014/09/30 13:43:06]

This file has been removed.

+
+# uncomment to remove the users
+GRANT USAGE ON *.* TO 'readonly'@'%';

[tfarina, 2014/09/29 18:55:27]

what '%' means? is it a shortcut to 'localhost'?

+GRANT USAGE ON *.* TO 'readwrite'@'%';
+DROP USER 'readonly'@'%';
+DROP USER 'readwrite'@'%';
+
+CREATE DATABASE skia ;

[tfarina, 2014/09/29 18:55:27]

nit: space between skia and ;

+CREATE USER 'readonly'@'%' IDENTIFIED BY '$MYSQL_RO_PW';
+GRANT SELECT ON *.* TO 'readonly'@'%';
+CREATE USER 'readwrite'@'%' IDENTIFIED BY '$MYSQL_RW_PW';
+GRANT SELECT, DELETE, UPDATE, INSERT ON *.* TO 'readwrite'@'%';
+EOF