Parse port out of hostname if specified in ADOConnection::Connect.
Ditto for ADOConnection:PConnect.
ADODB_pdo: verify class member $_driver has been properly initialized
before checking if a method exists. Avoids potential fatal error
and instead returns value indicating failure if applicable.
ADODB_pdo_mysql: add functionality from ADODB_mysql
* SQLDate method for generating date formatting strings
* SelectDB method for changing selected database
* $metaTablesSQL string that includes table vs view detection
ADODB_pdo_mysql error resilience
* Include ADODB_pdo class definition if needed
* If a hostname is passed to connect, convert it into
  a proper DSN