descriptions of environment variables

[CallumBaston]

Is your feature request related to a problem? Please describe.
Some of the possible environment variables mainly "DOZZLE_TAILSIZE" have no clear descriptions as to what they do.

Describe the solution you'd like
A simple description of what the variable does.

Additional context
I believe that for anyone new docker or Linux in general may have no idea what tail is or what it means in this context.

[amir20]

That’s a good idea. I had planned to do it but we just had a baby. So it will have to wait a little.

IMO the best place to add description would in be in the CLI flags.

[CallumBaston]

Congratulations Amir on your baby!
It is most likely better to add the descriptions for the CLI option of "--tailSize".

[amir20]

@CallumBaston I quickly added some help messages in 3cfd03e. Send a PR if you think more clarification is needed.

[CallumBaston]

Nope, Looks all good