[trean] Import bookmarks without any category defined

[Chuck Hagenbuch]

Quoting Chih-Wei Yeh <cwyeh at pest.yichi.org>:

>   One of my user found that, if you haven't defined any category for your
> trean bookmarks, importing bookmarks is possible, but the imported data
> will not be displayed correctly. I noticed that it's impossible to add a
> bookmark without any category defined. However, by the imported function,
> it's possible for a new user to import his data without define a
> category and fails. Could anyone help to resolve this problem by setting
> up some restriction for the importing function? Or, for the best case, is
> it possbile for users to import their bookmarks at top level without
> errors?

I've cleaned it up to disallow uploading when there are no categories. It'd be
great to eventually be able to store bookmarks in the top-level category, but
no one has had time to implement that yet.

-chuck

-- 
"But she goes not abroad in search of monsters to destroy." - John 
Quincy Adams