Reuse postgres connection by default

[groupnet]

This is a follow up to bugfix #349 (breaking change).

Intention
To be inline with the default behavior of pg-connect(...), make the connection without PGSQL_CONNECT_FORCE_NEW by default (see PHP manual: pg-connect). This might increase performance on frequent re-connections.

Straight forward approach
master...groupnet:PostgreDriver_persistent_bydefault

Question
To avoid confusion with the persistent postgres connection via the php function 'pg_pconnect(...)' (see PHP manual: pg-pconnect), I wanted to ask if you prefer to add new dibi parameter, eg. forcenew instead of using the existing parameter persistent as suggested in the approach above.

If no: I will make a pull request with the above approach.
If yes:

• what should be the name of the new parameter? forcenew?
• do you want me to implement another if-clause to also cover the persistent connection via pg_pconnect(...)?

[dg]

That would be good if someone using PostgreSQL can comment…

Because I don't care. I just don't want to listen to complaints that something has broken :-)

[groupnet]

The pull request #370 is my new approach to this issue:

• non-breaking change
• still gives the user to switch to PHP default: config['connect_type'] = 0;