change(idf): Rename component example

Author: lucasssvaz

Diff for: idf_component.yml

@@ -87,4 +87,4 @@ dependencies:
     version: "1.0.3"
     require: public
 examples:
-  - path: ./idf_component_examples/Hello_world
+  - path: ./idf_component_examples/hello_world

Diff for: idf_component_examples/Hello_world/CMakeLists.txt renamed to idf_component_examples/hello_world/CMakeLists.txt

@@ -12,13 +12,13 @@ To create a ESP-IDF project from this example with the latest release of Arduino
 ESP-IDF will download all dependencies needed from the component registry and setup the project for you.
 
 If you want to use cloned Arduino-esp32 repository, you can build this example directly.
-Go to the example folder `arduino-esp32/idf_component_examples/Hello_world`.
+Go to the example folder `arduino-esp32/idf_component_examples/hello_world`.
 First you need to comment line 6 `pre_release: true` in examples `/main/idf_component.yml`.
 Then just run command: `idf.py build`.
 
 ## Example folder contents
 
-The project **Hello_world** contains one source file in C++ language [main.cpp](main/main.cpp). The file is located in folder [main](main).
+The project **hello_world** contains one source file in C++ language [main.cpp](main/main.cpp). The file is located in folder [main](main).
 
 ESP-IDF projects are built using CMake. The project build configuration is contained in `CMakeLists.txt`
 files that provide set of directives and instructions describing the project's source files and targets