Need `--version` flag

[Danny Ben Shitrit]

I would like to suggest adding --version / -v flag. It is helpful in scripts for determining if an update is needed etc, and is a common practice.

(I am aware of the fact that the version is at the top of the help).

[Phil Eaton]

Done https://github.com/multiprocessio/dsq/releases/tag/0.8.0

[Danny Ben Shitrit]

This was fast, thanks!