0.2.0.0

• Rework the API
  • Introduce the SQLite a type instead of Database -> IO a for run, runWith, withDB, migrate, and so on.
  • Introduce withPool and export liftIO, fromString and void.
  • Depend on unliftio-core and mtl.
• Implement nested transactions via savepoints.
  • asTransaction renamed to transaction
  • cancelTransaction split to rollback and rollbackAll