Implement dsn support for connect() method

[artembo]

Pep 249 suggests a constructor method of Connection objects .connect()

It takes the following parameters as arguments:

Parameter	Meaning
dsn	Data source name as string
user	User name as string (optional)
password	Password as string (optional)
host	Hostname (optional)
database	Database name (optional)
kwargs	It is not from the standard but we use it for the method signature scalability.

Implement dsn parser utility to pass the settings to the Connection init by only one line.

The pattern can be used ([[[username[:password]@]host:]port)