add version to CSS

[yegor256]

Now it's not clear what is the exact Tacit version delivered to the browser. Would be convenient to put a small comment to our final CSS:

/* tacit 1.5.5 */

It should be present both in full CSS and in the minimized one.

[yegor256]

@filfreire what do you think?

[filfreire]

@yegor256 I agree, what we had previously got removed with the css_purge task that removed duplicate css rules. I will try to submit a PR to fix this later.

[yegor256]

@filfreire we just need to see the version, that's it