`put` returns the number of bytes actually transferred
from the input buffers.
Actions Required:
* Return the number of bytes actually transferred from the
input buffers in user defined `Body::writer::put` functions.
fix#550
* default body limits are now 1MB/8MB
* default header limit is 8KB
Actions Required:
* Call body_limit and/or header_limit as needed to adjust the
limits to suitable values if the defaults are insufficient.
The is_deferred nested type is removed from the BodyReader
requirements.
Performance for sending messages with `file_body` was cut
almost in half with is_deferred as `std::true_type` since
it caused double the number of socket writes. If the
deferred behavior is absolutely necessary, callers can get
the same effect by manually sending the headers first.
Actions Required:
* Callers who need the behavior of is_deferred as `std::true_type`
should manually construct a serializer and serialize the header
first, followed by the body.
fix#322
The new callback is informed of all frame types including close.
Actions Required:
* Change calls to websocket::stream::ping_callback to use
websocket::stream::control_callback
* Change user defined ping callbacks to have the new
signature and adjust the callback definition appropriately.
Actions Required:
* Change calls to msg.prepare to msg.prepare_payload. For messages
with a user-defined Fields, provide the function prepare_payload_impl
in the fields type according to the Fields requirements.
* FieldsReader now requires chunked() and keep_alive()
* serializer logic calls into the reader to calculate
the message metadata
* Removed some of the previous requirements of FieldsReader
Actions Required:
* Implement chunked() and keep_alive() for user defined FieldsReader types.
* `parser` is now templated on Allocator
* `parser` only produces messages using `basic_fields<Allocator>`
as the Fields type.
* message-oriented read and async_read only work on messages
using basic_fields as the Fields type.
Actions Required:
* Callers using `parser` with Fields types other than basic_fields
will need to create their own subclass of basic_parser to work
with their custom fields type.
