A better way to do disable-default-theme

Once disable-default-theme is specified in zk.xml, all CSS, including norm*.css.dsp and layout.css.dsp (and potential others). It is error proning to maintain them in zk.xml.

The better spec will be

<desktop-config>
<disable-theme-uri>~./zul/css/norm*.css.dsp*</disable-theme-uri>
<theme-uri>~./zul/css/normsm*.css.dsp*</theme-uri>
</desktop-config>