Bump to spark 2.4.5 + minor improvements

Remove sparklyr from datascience notebook

[ci skip] Show jupyter/datascience-notebook tags on the wiki

Follow on from #998

Translate '/docs/locale/en/LC_MESSAGES/index.po' in 'pt_BR'

translation completed for the source file '/docs/locale/en/LC_MESSAGES/index.po'
on the 'pt_BR' language.

Create apply_tags

Bump version of R packages

Co-Authored-By: Peter Parente <parente@gmail.com>

Co-Authored-By: Peter Parente <parente@gmail.com>

Address code review.
- Added apply_tags to post_push
- Verified output for versions

chore: Replace ADD with COPY

Julia prints a bit more so we make it conformant with the rest.

Draft!

Fix ssh deploy key format

New Docker Hub UI loses newlines in the env
var settings. Loss of new lines leads ssh-add
to prompt and fail when loading the key.

Base64 encode and decode the key to workaround
the limitation.

Fall back on symlink if mv fails

bump version numbers and add periods before *

Signed-off-by: Greg <werner.greg@gmail.com>

install pip explicitly

it should be there automatically, but no harm in being explicit

scipy-notebook: update bokeh

Bump Ubuntu 18.04 to latest build

Bump: notebook (6.0.0 > 6.0.2), jupyterhub (1.0.0 > 1.1.0), jupyterlab (1.2.1 > 1.2.5).