* Split the component automatic initialization to component automatic initialization and main funciton;
* Fix RT_IDLE_HOOK spelling issue;
* Add thread waiting for message queue when queue is full;
* Fix the issue of delete mq in `rt_mq_create` in some abnormal case;
* Remove the C++ keywords in the`rt_console_set_device`function;
* Remove the `suspend_thread_count` member from memory_pool structure;
* Fix the issue when block = NULL in rt_mp_free;
* Fix the issue of critical protection when `rt_thread_delete` change the status of thread;
## Components
* Fix the issue of mPool size in C++ / Queue;
* Add the error status return in C++ / Thread task join/wait function;
* Fix compilation warning in DFS/ELM FatFS;
* Add support for Linux NFS Server in DFS/NFS;
* Fix mkfs issue in DFS/UFFS;
* Add ftruncate, flock, getuid, umask APIs;
* Fix the display issue of fd with offset in list_fd command;
* Add `dfs_mount_device` API to mount a file system on a device which is already in mount_table;
* Rename the C++ keywords in DFS/rename function;
* Connnect dfs/poll, select with RT_USING_POSIX in Kconfig;
* Optimize the part of the code of finsh to make it more simple;
* When RT_USING_DEVICE is not used, finsh can use the `rt_hw_console_getchar()` function which is simple to implement and not using the device framework;
* Increase the line length of the finsh shell to more than 256 characters;
* utest can support clang compiler and C++ compiler;
* Fix possible cross-boundary issues in ulog;
* Fix compilation warning in `ulog/ulog_console_backend_output`;
* Add support for file sending and receiving feature in YModem;
* CRC16 can be calculated without the lookup talbe to reduce code size in YModem component;
* Fix the issue that stack may be wrongly released during pthread/destory;
* Fix the possible memory leaks issue which caused by pthread_create abnormal case;
* The timer-related APIs under different compiler of libc are moved to the `libc\compilers\common` folder;
* Remove redundant definitions in `dlib/sys/unistd.h` (which will cause compilation warnings);
* Add `sys/errno.h` and`sys/signal.h` header files under dlib;
* Freemodbus is no longer in the kernel, and split it as a standalone softwre package;
* AT socket updated to v1.3.0:
- Add multi-client and multi-device function support in AT Socket, and improve the dirty data handling when AT device hardware module reboot;
- Support netdev network card feature, which can manage and control AT device network connection through the network card interface;
* Improve AT Server function support in AT components, add AT Server data sending and receiving interfaces `at_server_send ()` and `at_server_recv ()`;
* Fix the issue of `closesocket()` in SAL component when socket closing failure after `shutdown()`;
* Improve `sal_bind ()` network card binding related function in SAL component;
* Add IPV6 related options configuration and function support to SAL and netdev;
* Improve ping command error handling and log display in the netdev;
* Add hostname configuration options and functions in lwIP component;
* Fix the assertion issue of `sys_arch_mbox_fetch()` in lwIP which may occur when a socket is closed;
* Add network card uninstallation function and support for dhcpd service stop function to the lwip component;