feat: Add ESPRESSIF MIT License

LICENSE

@@ -0,0 +1,22 @@
+
+ ESPRESSIF MIT License
+
+ Copyright (c) 2018 <ESPRESSIF SYSTEMS (SHANGHAI) PTE LTD>
+
+ Permission is hereby granted for use on all ESPRESSIF SYSTEMS products, in which case,
+ it is free of charge, to any person obtaining a copy of this software and associated
+ documentation files (the "Software"), to deal in the Software without restriction, including
+ without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ and/or sell copies of the Software, and to permit persons to whom the Software is furnished
+ to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice shall be included in all copies or
+ substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+