allow to set path to varnishstats

[frisi]

this is useful for hosts running multiple varnish instances with different binaries.

is there any other documentation that needs to be updated?

what about adding a changelog file where all contriubutors can document their changes?

[frisi]

@aouyar could you please review this and other open pull requests? (as you did the last commit and apparently merged the pr yourself, i'm asking you)