- connection initialize moves to a connection pool event [ticket:1340]

- connection initialize moves to a connection pool event [ticket:1340]
- sqlite doesn't support schemas.  not sure if some versions do, but marking those as unsupported for now.
- added a testing.requires callable for schema support.
- standardized the "extra schema" name for unit tests as "test_schema" and "test_schema_2".
- sqlite needs description_encoding (was some other version of pysqlite tested here ?)
- other test fixes.