Fixed #216. Added wrapper/helper classes AMQPArray & AMQPTable, which may be directly passed to AMQPWriter::write_array() & write_table()
examples now use AMQPTable
Fixed 'b' type to be read as short-short-int, as per amqp spec. 
Added few data types
made read_value() private, just like its counterpart write_value()
Took care of field types mess - http://www.rabbitmq.com/amqp-0-9-1-errata.html#section_3
By default rabbitMQ set is used
reverted Decimal to use signed long as per http://www.rabbitmq.com/amqp-0-9-1-errata.html#section_3
removed unused ArrayAccess iface from AMQPAbstractCollection
Incoming message headers as AMQPTable, easily retrievable in their original form via getNativeData()
Added examples for message headers
fixed test for 32bit systems