Dev mode that drops and recreates a keyspace for developer productivity

[eighty4]

Developer workflows for adding new statements to a CQL file that's already been migrated to a local cassandra. There are two current approaches:

• Add new CQL files to migrate that will be merged into a single CQL file when development work is ready to be committed
• Repeatedly drop keyspace ... with cqlsh and rerun cquill migrate

Hibernate and Flyway supports dropping and recreating schemas for developer experience. This could be replicated with a --refresh or --dev-refresh flag on the migrate command.

I'm hesitant about introducing this as a param that could accidentally get ran against a production database. Another option would be to introduce a new command called dev that would behave like migrate with the extra step of removing the existing keyspaces.