Logging in series of examples has misuse of "%d" instead of type-appropriate format specifiers.
Fix by changing "%d" to PRIxx macros corresponding to type.
Remove -Wno-format compile flag in those examples that are affected.
- Removes extra callback function, the code from the callback is integrated into the event handler code.
- Clarify usage of handler args, pass NULL as callback data instead of client, to avoid user confusion,
and add documentation on usage of handler_args.
esp_netif_init() returns standard esp_err_t error code (unlike tcpip_adapter init), so shall be checked for the return value
Also to make the initialization code more consistent.
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
