Bug 1490107

Description of problem:
In bug https://bugzilla.redhat.com/show_bug.cgi?id=1269970 Miguel Martin (comment 11) suggested an alternative method of configuring sysprep (i.e. not using the engine-config) by making a copy of the default sysprep.

This method has the advantage not needing to restart the engine.
This method has been approved by Yaniv Kaul but needs to be verified by QE before it can be added to the documentation.

1. Install a Windows Machine, seal it, and create a template from it, just as described in the KCS.
2. Create a pool based on the previous template with sysprep customization.

For this solution, we will specify the user/pass and the product key using a custom sysprep (in pool 'Initial Run' tab), that is, a copy of the default sysprep.
In case of a Windows 7 x64 os, the default sysprep is in file '/usr/share/ovirt-engine/conf/sysprep/sysprep.w7x64'.

So, once we pasted the content of the file in the 'sysprep' textbox (in the pool 'Inital Run' tab) we modify the following info:

......
                <ProductKey>
                    <Key><![CDATA[$ProductKey$]]></Key>  ----------------------> with <Key>xxxx-xxx-xxx-xxx</Key>
                </ProductKey>
.....
                <Credentials>
                    <Domain><![CDATA[$JoinDomain$]]></Domain>
                    <Password><![CDATA[$DomainAdminPassword$]]></Password>  ----------------------> with the domain password<Password>mypassword</Password>
                    <Username><![CDATA[$DomainAdmin$]]></Username> ----------------------> with the domain admin user<Username>DomainAdministrator</Username>
                </Credentials>
......

There is no need to modify rest of the variables in the xml as they can be filled from the 'Initial Run' tab fields (Domain, OU, Organization Name, Custom Locale..)
Well, maybe I would modify the local user admin named 'user',:

......
           <UserData>
            ..........
                <FullName>"user"</FullName> <----------------------------- with <FullName>"mylocaladmin"</FullName>
            ..........
            </UserData>
......
               <LocalAccounts>
                    <LocalAccount wcm:action="add">
                        <Password>
                            <Value><![CDATA[$AdminPassword$]]></Value>
                            <PlainText>true</PlainText>
                        </Password>
                        <DisplayName>user</DisplayName> <----------------------------- with <DisplayName>mylocaladmin</DisplayName>
                        <Group>administrators</Group>
                        <Name>user</Name> <----------------------------- with <Name>mylocaladmin</Name>
                    </LocalAccount>
                </LocalAccounts>
.........