Travis showing DOCTR secure keys in the matrix list

[asmeurer]

See for example https://travis-ci.org/github/sympy/sympy. It makes it hard to see the actual environment variables that are used to differentiate jobs.

We might

1. Suggest people to put the secure key only on the matrix build that needs it.
2. Rename the environment variable to something like _DOCTR_DEPLOY_..., assuming that makes it list after the other ones.

[asmeurer]

I asked on the Travis forum if there is a way to hide them https://travis-ci.community/t/hiding-secure-environment-variables-from-the-build-page/7544

[asmeurer]

It looks like they order things based on the order they appear in .travis.yml, not alphabetically. I think the solution to this is to have people put the environment variable in the matrix section instead of the global section. This is better anyway because it will make the variable only available to the build that actually needs it.

Here's an example of that change https://github.com/Quansight/versioned-hdf5/pull/50/files.