mgr/dashboard: Add dashboard node script

mgr/dashboard: Add dashboard node script

This file should be used to agregate all external scripts we need.
Multiple flags can be used in the same call.

Available flags:

--env: Generates angular environment files.

--pre: Modifies 'angular.json' to enable the build of custom locales using
       angular --localize.
       Languages can be defined using the environment variable LANGS,
       if no value is provided all languages will be build.
       Default language is always build, even if not provided.
       p.e.: 'LANGS="pt" node cd --pre', will build EN and PT.
       For backward compatibility we accept both long and short version of
       languages, p.e.: 'pt' and 'pt-BR'

--post: Restores 'angular.json' to its original.

Signed-off-by: Tiago Melo <tmelo@suse.com>