API-93 - use rel links for pagination

https://clever.atlassian.net/browse/API-93
`CGI.parse` returns query string in this format:

```ruby
{ key1 => [value1, value2, ...], ... }
```

The values are always an array, even if there is only one binding for that key. It's done this way to support a key being assigned multiple times in a query string.

I just opted to go for the first one. Tell me if this is a bad assumption