Fix npm warning

[NetOpWibby]

Apparently, --omit=dev should be used over --production.

[rtdev-com]

Need to fix a typo

[pinheadmz]

grep the repo for production, there are two more places to change I think: Dockerfile and CONTRIBUTING.md can you find anything else like this that needs to be updated?

[NetOpWibby]

grep -irn "\-\-production" shows:

./Dockerfile:9:RUN npm install --production
./docs/install.md:36:npm install --production
./CONTRIBUTING.md:23:"developer dependency" if installed without the `--production` flag. The

[NetOpWibby]

@pinheadmz All set!

[pinheadmz]

CI was failing on node v12 which is unsupported now anyway. Removing that so this docs-only PR will pass integration tests!

[pinheadmz]

Ugh, @chjj's DNS seed server is down. I'm gonna fix this flakey test by targeting nic.com a much more reliable name for lookups.

[coveralls]

Coverage decreased (-0.2%) to 67.744% when pulling 8f062c3 on NetOpWibby:patch-1 into 395878a on handshake-org:master.

[pinheadmz]

Ugh part III: Fine lets just skip the test that requires external DNS lookups, for now.