Mark requests to rocks server

[artur-barsegyan]

We want to analyze rock usage. General issue is here: tarantool/rocks.tarantool.org#20.

It would be helpful to distinguish rock downloads:

• via cartridge-cli`s pack stage
• via tarantoolctl CLI interface
• etc

It helps us with understanding: which instrument is more widespread and what the correlation between tool and rocks that are installed.

(but we need to push some functionality to tarantooctl for the feature support)

[Totktonada]

I'll move it to a wishlist for a while: if we'll do so, it worth to do the whole thing: rocks.tarantool.org support, changes in our luarocks fork, possibly changes in tarantoolctl and, finally, here. Possibly it would spread over several teams, so it should reach us as part of the product plan.