Setting up a JSON configuration file to change LED paths without recompiling

Setting up a JSON configuration file to change LED paths without recompiling

v1

- the change allows the paths to the LED folders to be changed without
  having to recompile the widget
- the JSON file itself is included in this commit with the name "hvac.json"
- the location which the parser expects the configuration
  file to be in is /etc

v2

- optimised code in terms of opening and closing paths for writing
- put afb header definitions together

v3

- removed all caps warning notifications

Change-Id: If075c6650d8802849cbd706be4adbca9f1996c9e
Signed-off-by: Yordan Dimitrov <y.dimitrov.14@gmail.com>