Ensure dseq supports being passed a list of inputs

I was struggling to get `dseq` to work with a list of input sources from a glob:
```clojure
(seqf/seq (fs/path-glob "/*.blah"))
```
But this does not work since you have to call seq with apply:

```clojure
(apply seqf/dseq (fs/path-glob "/*.blah")))
```

Since the & paths is a list of lists in the first example:
https://github.com/damballa/parkour/blob/master/src/clojure/parkour/io/seqf.clj#L12

This felt a bit odd so I thought I would suggest a patch to allow both forms to work. I've tried to maintain the existing api and avoid any breaking changes.

Warning: written without :coffee: