Adds constants within the class for protocols; Refs #6
Checks if request method is secure; Refs #6

*   Valid request methods: `GET`, `POST`, `PUT`, `DELETE`, PATCH`
*   If not any of these, 'OTHER' is returned
Implements `ChangeProtocol` function; Refs #6

*   Checks for current scheme and changes `http` to `https` and vice
*   versa;
Minor fix: Was using `RequestURI` in place of `Path`; Refs #6

*   `RequestURI` contains query string by default and hence suitable for
*   use directly in `ChangeProtocol` method