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New features:
* Transparent automatic reconnects if database disappears and comes back.
* Session init commands (``setsession``).
* Dynamic pool size stretching. New connections will be opened under
load up-to predefined limit.
* API for manual connection management with ``getconn``/``putconn``. Useful for server-side cursors.
* A lot of internal improvements and cleanup.
Fixes:
* Connections are managed explicitly - eliminates transaction problems reported.
* ``connection_factory`` (and ``curosr_factor``) arguments handled properly by ``Pool``.