fixing detection of multiple feeds of the same type

if there are multiple feeds of the same type on one page:

```
<link rel="alternate" type="application/atom+xml" title="feed one - atom" href="http://example.com/feed.atom" />
<link rel="alternate" type="application/atom+xml" title="feed two - atom" href="http://example.com/feed-two.atom" />
<link rel="alternate" type="application/rss+xml" title="feed one - rss" href="http://example.com/feed.atom" />
```

only the first and the last would be returned by the `feeds` method.

this is obviously suboptimal and this pr fixes it.