Unexpectedly serves files from outside the given ROOT directory.

live-server is serving files outside the given directory and this is unexpected: ``` ## Create new empty test directory that we want to serve from: mkdir test cd test echo "hello" > index.html live-server -p 8000 ``` Open the URL `http://localhost:8000//etc/passwd` and see that files are served from outside the given directory. There should be a check to make sure that the paths served are not from any parent directory.