Fixed list_display to match screenshot and fixed double registration error

1. list_display was not matching the order of the screenshot below
2. adding the extra line ``admin.site.register(Page, PageAdmin)`` produces "the model "Page" is already registered" error we have to modify the registration
Merge pull request #21 from michaelchum/master

Fixed list_display to match screenshot and fixed double registration err... (courtesy of @michaelchum)