fix#248
This additionally invokes the pong callback for received pings, allowing
callers to more efficiently detect when a connection is still lively:
* pong_callback renamed to ping_callback
* Callback signature has an extra `bool` to indicate if the received
control frame is a ping or pong.
fix#171
Several names and HTTP identifiers are renamed to be
more consistent, self-explanatory, and concise:
* "Fields" is a collection of HTTP header fields (rfc7230 section 3.2)
* "Header" is the Start Line plus Fields. Another way to look at it is,
the HTTP message minus the body.
* `basic_fields` replaces `basic_headers`
* `fields` replaces `headers`
* `Fields` replaces `Headers` in template parameter lists
* `header` replaces `message_headers`
* `header::fields` replaces `message_headers::fields`
The changes are cosmetic and do not affect run-time behavior.
ext_list:
Iterable container of comma separated extensions, where each extension
is a token followed an optional list of semicolon delimited parameters,
with each parameter consisting of a name / value pair. The value can
be a token or quoted-string.
param_list:
Iterable container of semicolon delimited parameters, where each parameter
is a name / value pair. The value can be a token or quoted-string.
token_list
Iterable container of comma delimited tokens.
* Remove obsolete rfc2616 functions
* Refactor and consolidate case-insensitive string helpers
* Improve test coverage
* tests for invokable in composed ops
* Update documentation
* Add License badge to README
* Target Windows 7 SDK and later
* Make role_type private
* Remove extra unused masking functions
* Allow stream reuse / reconnect after failure
* Restructure logic of composed operations
* Allow 0 for read_message_max meaning no limit
* Respect keep alive when building HTTP responses
* Check version in upgrade request
* Response with 426 status on unsupported WebSocket version
* Remove unnecessary Sec-WebSocket-Key in HTTP responses
* Rename to mask_buffer_size
* Remove maybe_throw
* Add ping, async_ping, async_on_pong
* Add ping_op
* Add pong_op
* Fix crash in accept_op
* Fix suspend in close_op
* Fix read_frame_op logic
* Fix crash in read_op
* Fix races in echo sync and async echo servers
