[GRASS-git] [OSGeo/grass] 400349: Update of travis configuration for Python 3 (#115)

[Markus Neteler]

  Branch: refs/heads/master
  Home:   https://github.com/OSGeo/grass
  Commit: 400349708525d11b6b1d819f3b954a4cd1ee3d31
      https://github.com/OSGeo/grass/commit/400349708525d11b6b1d819f3b954a4cd1ee3d31
  Author: Markus Neteler <neteler at gmail.com>
  Date:   2019-08-31 (Sat, 31 Aug 2019)

  Changed paths:
    M .travis/linux.install.sh
    M .travis/linux.script.sh

  Log Message:
  -----------
  Update of travis configuration for Python 3 (#115)

- layout sync with Dockerfile
- add zstd support
- update package names to Python 3