[GRASS-git] [OSGeo/grass] 02db1b: Update of travis configuration for Python 3

[Markus Neteler]

  Branch: refs/heads/travis_config_updates
  Home:   https://github.com/OSGeo/grass
  Commit: 02db1b6c10cd60a79dbf784747d8bcc529ae44fc
      https://github.com/OSGeo/grass/commit/02db1b6c10cd60a79dbf784747d8bcc529ae44fc
  Author: Markus Neteler <neteler at mundialis.de>
  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

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