Allow "break" as substitute for stepcode "0" in strings, with unit test

Support the string literal "break" as human readable substitute for
stepcode 0 on translation from strings. String getters already performed
that substitution.
Don't localize values returned in scientific notation (report and
fix by Snickermicker)

Strings holding bigger floating point values use scientific notation,
which should not get formatted according to the current locale for
consistency.
Add test for non-localized formatted strings of floating point values