ADS-7
Added advert preview page on step 4 and preview page on /advert/%nid,
Advert view is now on /advert/%nid,
Advert adding is now on /advert/add,
Advert editing is now on /advert/%nid/edit,
ADS-7
Attachments are now displayed on the advert preview page when adding new advert
ADS-7
Code style changed to conform to Drupal coding standards
ADS-7
Fixed notice when advert has no references to category-related nodes
Merge pull request #8 from nseam/master

Working advert adding, editing and previewing