[PATCH 1/3] Drop support for Python 3.4, add Python 3.7

[Stephen Finucane]

On Tue, 2019-09-03 at 18:03 +0100, Stephen Finucane wrote:
> It's no longer supported upstream and the *second* last Ubuntu LTS
> release provides something newer. Time to move on.
>
> Signed-off-by: Stephen Finucane <stephen at that.guru>

I've applied this albeit with a couple of other fixes I missed
(.travis.yml and a release note) since it was blocking some dependency
updates.

Stephen