v1.3.2: Merge pull request #31 from mathroc/master

fix code against a subtype

v1.3.1: Merge pull request #30 from mathroc/fix/28

Unwrap exceptions

postgresql improvements

Merge pull request #27 from mathroc/feature/postgresql-master-slaves

add PostgresqlMasterSlavesDriver & improve PostgreSQLRetryStrategy

v1.2.0

Merge pull request #25 from mathroc/feature/postgresql

Add PostgreSQLRetryStrategy

v1.1.0: Merge pull request #24 from mathroc/feature/retry-pdo-statement

Retry Statement->execute() too

v1.0.0

Merge pull request #23 from mathroc/feature/too-many-connections

handle Too many connections