🚀 v2.1.2 Add `upsert` and `mrsm_temp_tables`.

v2.1.1 – v2.1.2

• Add upsert for high-performance pipes.
  Setting upsert under pipe.parameters will create a unique index and combine the insert and update stages into a single upsert. This is particularly useful for pipes with very large tables.

  import meerschaum as mrsm
  
  pipe = mrsm.Pipe(
      'demo', 'upsert',
      instance = 'sql:local',
      columns = ['datetime', 'id'],
      parameters = {'upsert': True},
  )
  
  mrsm.pprint(
      pipe.sync(
          [
              {'datetime': '2023-01-01', 'id': 1, 'val': 1.1},
              {'datetime': '2023-01-02', 'id': 2, 'val': 2.2},
          ]
      )
  )
  #  🎉 Upserted 2 rows.

• Add internal schema _mrsm_internal for temporary tables.
  To avoid polluting your database schema, temporary tables will now be created within _mrsm_internal (for databases which support PostgreSQL-style schemas).

• Added mrsm_temporary_tables.
  Temporary tables are logged to mrsm_temporary_tables and deleted when dropped.

• Drop stale temporary tables.
  Temporary tables which are more than 24 hours will be dropped automatically (configurable under system:sql:instance:stale_temporary_tables_minutes).

• Prefix instance tables with mrsm_.
  Internal Meerschaum tables still reside on the default schema but will be denoted with a mrsm_ prefix. The existing instance tables will be automatically renamed (e.g. pipes will become mrsm_pipes) to add the prefix (this renaming detection will be removed in later releases).

• Fix an issue with bootstrap.
  Refactoring work for 2.1.0 had broken the bootstrap action.

• Fix an issue with pause jobs.

• Fix an issue when selecting inverse pipes.
  Null location keys are now coalesced when selecting pipes to produce expected behavior.

• Avoid a system exit when exiting the SQL CLI.