This commit introduces the necessary machinery to authenticate with
ILIAS and crawl the home page.
It can't do much yet and just silently fetches the homepage.
These options are meant to make the local crawler behave more like a
network-based crawler for purposes of testing and debugging other parts of the
code base.
Path should only be used when we need to access the file system. For all other
purposes (mainly crawling), we use PurePath instead since the paths don't
correspond to paths in the local file system.
