tcp_transport/ws_client: websockets now correctly handle messages longer than buffer
Closes IDF-1084 and IDF-1083
See merge request espressif/esp-idf!6740
transport_ws can now be read multiple times in a row to read frames larger than the buffer.
Added reporting of total payload length and offset to the user in websocket_client.
Added local example test for long messages.
Closes IDF-1083
tcp-transport component did not support wait forever. this update uses value of -1 to request this state.
websocket client uses timeouts in RTOS ticks. fixed recalculation to ms (including special value of -1) to use correctly tcp-transport component
Closes https://github.com/espressif/esp-idf/issues/4316
tcp_transport component used public header files such as 'transport.h', etc. which are too generic and might collide with user or user libraries headers
This change closes#2417
Four internal APIs `esp_http_client_connect()`, `http_client_prepare_first_line()`, `esp_http_client_request_send()` and
`esp_http_client_send_post_data()` API have been added for perfoming connection establishment (sync as well as async),
preparing first line, sending request and sending post data respectively.
In `transport_ssl`, `ssl_connect_async()` API has been added for establishing asynchronous connection.
added docs and tests for mqtt library, small fixes (removed warnings, option for custom outbox, websocket bug fixed for longer transports). refactored to use common tcp_transport component, support for CMake build system.
Closes#2108
