Fix/panic

[panaC]

Fixes #11

cc @llemeurfr

[panaC]

In Go, a slice already behaves like a small reference-like value.
A []stor.Publication is a header containing:

• pointer to array
• length
• capacity

So passing or returning a slice copies only that small header, not the whole publication array. That means *[]stor.Publication usually gives no useful performance benefit.
I don't think any mutation of the publication slice pointer is required here. Maybe I'm wrong.

[panaC]

Add a pointer to the slice is more risky as it can carry a NULL reference

[panaC]

Overall, I think Go main weakness is the lack of borrow checker, which makes this kind of error possible. I'm afraid there is no compile-time static checker to catch it.