Add an align_columns option to schedule generation. When enabled, each
keyword is serialized with a '--'-prefixed column-header comment and data
rows right-aligned into fixed-width columns, instead of the compact default
form. The default output is unchanged.
A new RimKeywordFactory::deckKeywordToAlignedString introspects the OPM deck
model and renders each item in its own column (consecutive defaults are not
collapsed into 'N*'). The flag is threaded through RicScheduleDataGenerator
and exposed on the GenerateSchedule scriptable method as align_columns in the
Python generate_schedule_text wrapper.