CI update

[davidanthoff]

This updates our general CI config. Changes are:

• Use travis instead of appveyor for testing on Windows. Seems faster and one less moving part.
• Run tests on Julia 1.1. I think if we declare compat with that version, we should test it.
• Use the coveralls flag in travis instead of the manual code version.

This should probably go hand-in-hand with deleting the appveyor project.

[giordano]

Wow, segmentation faults 🙂

[davidanthoff]

And we don't seem to have a julia 1.1 image for the drone build? Who is maintaining these, and is there a chance that we can add that?

[giordano]

They removed Julia 1.1 while upgrading to 1.2: docker-library/julia@5f637f2 I guess because 1.1 is unmaintained

[coveralls]

Coverage decreased (-0.2%) to 91.198% when pulling 577f6f6 on davidanthoff:ci-update into 15706f2 on JuliaGraphics:master.

[coveralls]

Coverage decreased (-0.1%) to 91.204% when pulling 577f6f6 on davidanthoff:ci-update into 15706f2 on JuliaGraphics:master.