Add a multi channel example

Added a multi channel example with run limit, tilting and channel selection
features. Refs #1104 and closes #1111.

examples/relay_chn_multi/main/idf_component.yml

@@ -0,0 +1,8 @@
+dependencies:
+  idf:
+    version: '>=4.1.0'
+  espressif/button: ^4.1.1
+  espressif/led_indicator: ^1.1.1
+  relay_chn:
+    version: '*'
+    override_path: ../../../