Update python
Update python

Changes:

- https://github.com/docker-library/python/commit/f6e98ea: Update to 3.8.0a4, pip 19.1.1
- https://github.com/docker-library/python/commit/f233f51: Update to 3.5.7, pip 19.1.1
- https://github.com/docker-library/python/commit/34c9df3: Update to 3.7.3, pip 19.1.1
- https://github.com/docker-library/python/commit/00dfb84: Update to 2.7.16, pip 19.1.1
- https://github.com/docker-library/python/commit/4df1296: Update to 3.6.8, pip 19.1.1
- https://github.com/docker-library/python/commit/81d9938: Update to 3.8.0a3, pip 19.1.1

thresheek/official-images,docker-flink/official-images,docker-library/official-images,docker-solr/official-images,thresheek/official-images,infosiftr/stackbrew,jperrin/official-images,neo-technology/docker-official-images,docker-solr/official-images,docker-library/official-images,docker-library/official-images,dinogun/official-images,docker-solr/official-images,docker-flink/official-images,infosiftr/stackbrew,docker-flink/official-images,31z4/official-images,dinogun/official-images,thresheek/official-images,infosiftr/stackbrew,neo-technology/docker-official-images,docker-flink/official-images,docker-flink/official-images,thresheek/official-images,jperrin/official-images,jperrin/official-images,31z4/official-images,jperrin/official-images,infosiftr/stackbrew,docker-library/official-images,dinogun/official-images,neo-technology/docker-official-images,docker-solr/official-images,infosiftr/stackbrew,docker-library/official-images,dinogun/official-images,infosiftr/stackbrew,docker-flink/official-images,31z4/official-images,neo-technology/docker-official-images,neo-technology/docker-official-images,dinogun/official-images,thresheek/official-images,docker-flink/official-images,infosiftr/stackbrew,docker-solr/official-images,infosiftr/stackbrew,dinogun/official-images,thresheek/official-images,docker-library/official-images,jperrin/official-images,jperrin/official-images,docker-solr/official-images,docker-flink/official-images,jperrin/official-images,infosiftr/stackbrew,neo-technology/docker-official-images,docker-solr/official-images,docker-library/official-images,neo-technology/docker-official-images,infosiftr/stackbrew,31z4/official-images,dinogun/official-images,neo-technology/docker-official-images,docker-library/official-images,thresheek/official-images,docker-library/official-images,neo-technology/docker-official-images,infosiftr/stackbrew,docker-library/official-images,docker-library/official-images,neo-technology/docker-official-images,neo-technology/docker-official-images,31z4/official-images,docker-flink/official-images,dinogun/official-images,jperrin/official-images,thresheek/official-images,jperrin/official-images,neo-technology/docker-official-images,dinogun/official-images,thresheek/official-images,docker-solr/official-images,31z4/official-images,dinogun/official-images,infosiftr/stackbrew,31z4/official-images,docker-solr/official-images,infosiftr/stackbrew,31z4/official-images,docker-library/official-images,31z4/official-images,docker-library/official-images,thresheek/official-images,docker-solr/official-images,jperrin/official-images,31z4/official-images,dinogun/official-images,docker-solr/official-images,jperrin/official-images,thresheek/official-images,thresheek/official-images,31z4/official-images,jperrin/official-images,thresheek/official-images,31z4/official-images,docker-solr/official-images,docker-flink/official-images,docker-flink/official-images,docker-flink/official-images,dinogun/official-images,thresheek/official-images,docker-solr/official-images,infosiftr/stackbrew,31z4/official-images,dinogun/official-images,neo-technology/docker-official-images,docker-flink/official-images,31z4/official-images,docker-library/official-images,neo-technology/docker-official-images,jperrin/official-images,docker-solr/official-images