HG-367: Working version of new url parsing;

Major refactoring of the URL parsing method, moved from RegExp to array based processing.
This PR should solve #9 and the case is added to the test case.

The logic behind handling the legacy URLs:
- the URL is split into segments by `/`
- first two segments `http://` are removed;
- next segment is the domain name;
- next segment is the cachebuster value with `__cb` in front so we use `substr()` to get rid of the prefix;
- clearLegacyThumbSegments is called which clears the `thumb` and last segment from the URL if it is a thumbnail;
- the last three segments are the `imagePath` so we splice them from the array;
- what is left is the `wikiaBucket`, which is the first and the last element of the array, these get removed from the array
- what is left in `segments` (if any) are the prefix segments so they go to `pathPrefix`
Update JSDoc too (`@private`).