Remove --schema-name option

[rustprooflabs]

Details

The concept of changing schema name from osm conflicts with many of the features in PgOSM Flex. The --schema-name option will be removed. Users that want to rename the schema (I'm one of them) can manually ALTER SCHEMA as necessary. That makes the disconnect an obvious choice removed from PgOSM Flex, along with the expectation that "everything will just work." (It won't)

For my use cases where I rename the schema, having PgOSM Flex do that for me adds no value/time savings/etc.

I hope this isn't a negative impact to anyone. I've been thinking about this for a while and still think this is the right choice in the long run. Leaving this in as inviting someone to encounter a bad time with some unexpected disconnect/bug.