array of module configurations. Each array element represents a single module,
which can be either a string representing the module ID or an ID-configuration pair representing
a module with the specified ID and the initial property values.
<br/><br/>
For example, the following array declares two modules:
<pre>
array(
    'admin',                // a single module ID
    'payment'=&gt;array(       // ID-configuration pair
        'server'=&gt;'paymentserver.com',
    ),
)
</pre>
<br/><br/>
By default, the mo