Move loads() to load() and create a new loads() function that supports processing of a provided JSON string.

[Pedro Rodriguez]

Current loads() should be moved to load() and loads() should be a refactoring of the JSON parsing logic.
The new function should accept a path variable in order to process the includes or it will use the executing python script path as default.

• Refactor JSON String processing logic into loads()
• Update load() logic so it uses loads() to parse the json file.
• Update and add unit test in order to cover load and loads()
• Add logic to use execution python script as root for includes if loads includes_path is not provided.
• Allow relative path to be used in the include directive.
• Add Unitest