Travis and Docker use different Hugo versions.

[exitmouse]

Travis CI pulls the latest from github and uses that; Docker downloads a static release.
So if Hugo makes a breaking change in the year or so between updates of this site, Travis will require that we use the new syntax or it won't let us submit anything... but the site will break when deployed using the old Hugo via Docker, which won't support the new syntax.

[fish]

paging Dr. @ggilmore

[exitmouse]

The fix should be pinning travis to an old version--we should copy the code from the Dockerfile.