Failing to build a branch on Travis CI

[dahenson]

While attempting to build a branch of Agenda, Houston appears to fail on an outdated version of a file. The build log is here: https://travis-ci.org/dahenson/agenda/builds/574665731

The line it is failing on is no longer valid in the branch in question: https://github.com/dahenson/agenda/blob/develop/src/Agenda.vala#L44

I have been trying to find where in the Agenda source code this could be going wrong, but I've begun to suspect this is a Houston issue.

[padjis]

I am having a Houston issue while trying to run docker services based on ubuntu xenial on travis ci