Improve new resource screen - less technical

[joepio]

• Importer, class and property are very 'techical' resources. Class and Property are even more low-level, as they make up parts of other resources. Should we show them here? Thanks to @adileo.
• The class dropdown should maybe not be shown first
• Maybe use a select dropdown for the most important types (document / chatroom), and show an 'advanced' button to open the full new resource page