bugfix #245 show in navigation for custom navigation types

correct me when i'm false:
`pages without a parentFolder` are loaded over the `$objSelect2`
 and all *other pages* are loaded through *$objSelect1*. 

Then in the following structure:

page0
folder1
 - page12
 - page13

folder2
page3

page12, page13 are in the folder1 and folder when has a depth of 0 so in the select it is folders.depth >= 0 and not folders > 0