Force equal passwords in APS installer before form can be posted

The 'repeat password' field on the APS installer page does not enforce the inputted passwords to be equal. This PR fixes that problem by adding the class positive to the submit button. This makes the javascript only enable the submit button if the passwords are equal.

interface/web/sites/templates/aps_install_package.htm

@@ -57,7 +57,7 @@
 		<input type="hidden" name="install" value="0" />
 		<div class="clear">
 			<div class="right">
-				<button class="btn btn-default formbutton-success" type="button" value="{tmpl_var name='btn_install_txt'}" name="btn_install" onclick="document.pageForm.install.value=1; ISPConfig.submitForm('pageForm','sites/aps_install_package.php?id={tmpl_var name='pkg_id'}');">{tmpl_var name='btn_install_txt'}</button>
+				<button class="btn btn-default formbutton-success positive" type="button" value="{tmpl_var name='btn_install_txt'}" name="btn_install" onclick="document.pageForm.install.value=1; ISPConfig.submitForm('pageForm','sites/aps_install_package.php?id={tmpl_var name='pkg_id'}');">{tmpl_var name='btn_install_txt'}</button>
 				<button class="btn btn-default formbutton-default" type="button" value="{tmpl_var name='btn_cancel_txt'}" data-load-content="sites/aps_availablepackages_list.php">{tmpl_var name='btn_cancel_txt'}</button>
 			</div>
 		</div>