These lines need to be added to the postgresql_db database creation task to enable und-x-icu collation (sorting):
ICU collation is operating system independent.
und-x-icu (for “undefined”) is the ICU “root” collation. Use this to get a reasonable language-agnostic sort order: https://www.postgresql.org/docs/current/static/collation.html
"The CLDR root collation […] is used by all other locales by default, or as the base for their tailorings." http://www.unicode.org/reports/tr35/tr35-collation.html#Root_Collation
This fixes the problem that spaces are ignored when sorting. See
MODINVSTOR-149 for an example.