Added get_languages(), detect_language() functions and test cases for th...

*Added the get_languages() function to get a Python list of the supported language locale codes.
*Added detect_language() function to detect the language of the input text.
*Added test cases for both functions - Test cases pass with no failures.
Well, the `call` function assumes that the outputs are JSON, the getLanguages() output is an XML file and the output of the detectLanguage() function is,

    "en"
    None

Hence, the brand new functions.