Form\Generate and DB\Extend\ArrayIO split

Move DB\Extend\ArrayIO to internal class in variable and do not extend
Form\Generate from it (as we do not have a base class anymore, this is
no longer neded)

Update all calls in connected classes.

Add interface methods for DB\Extend\ArrayIO to interface with all class
vars that are now all private

www/includes/templates/admin/edit_elements.tpl

@@ -42,6 +42,7 @@
 			<textarea name="{$element.data.name}"{if $element.data.rows} rows="{$element.data.rows}"{/if}{if $element.data.cols} cols="{$element.data.cols}"{/if}>{$element.data.value}</textarea>
 		{/if}
 		{if $element.type == 'drop_down'}
+			{* {$element.data.selected} *}
 			{html_options name=$element.data.name values=$element.data.value output=$element.data.output selected=$element.data.selected}
 			{if $drop_down_input}
 				&nbsp;&nbsp;&nbsp;<input type="text" name="{$element.data.input_name}" value="{$element.data.input_value}"{if $element.data.input_size} size="{$element.data.input_size}"{/if}{if $element.data.input_length} maxlength="{$element.data.input_length}"{/if}>