Finished the Audiality 2 binding, as far as possible

Implemented Size(), Run(), Render() and NewWave().

Added T prefix to object type exports, and added the missing types.

Added state open flags SILENT, RTSILENT and NOSHARED.

Exporting constant WAVEPERIOD. (A2_WAVEPERIOD from waves.h.)

Retain(), Release(), Assign() and Export() now throw exceptions instead
of returning error codes. Note that Release() ignores A2_REFUSE!

Most of the features still not wrapped by the EEL binding are either
irrelevant without, or not possible to support without dedicated
asynchronous EEL VM states for realtime callbacks, and as there's no
easily accessible, thoroughly tested support for that yet (C API only;
no built-in inter-state synchronization or communication facilities),
we're leaving that out for now.