v1.6 backports 2019-12-12

[jrajahalme]

• Add missing words to spelling_wordlist #9643 -- Add missing words to spelling_wordlist (@ungureanuvladvictor)
• fqdn: Support setting tofqdns-min-ttl to 0 #9743 -- fqdn: Support setting tofqdns-min-ttl to 0 (@raybejjani)

Once this PR is merged, you can update the PR labels via:

$ for pr in 9643 9743; do contrib/backporting/set-labels.py $pr done 1.6; done

---

This change is 

[jrajahalme]

never-tell-me-the-odds

[aanm]

Can you drop the FQDN commit so we can fix the documentation parts?

[raybejjani]

@jrajahalme I finally managed to understand what's going on. The version of viper we have on master and 1.6 happen to have a bug were IsSet always returns true. This seems to cause IPs to not show up in the checks for the failing tests. Given that the original motivation for backporting this was to supports the --tofqdns-min-ttl 0 usecase, but it turned out to not be in-use, I'd say let's skip the backport for now. It isn't critical for any known user (and otherwise unlikely to occur).
See #9796 for the fix on master.

[jrajahalme]

Dropped #9743

[jrajahalme]

never-tell-me-the-odds