This file tree displays all the diff files in a tree like format
Each file is taken and converted into a tree with folders
Each folder can be toggled open & closed
Clicking a file will scroll to the diff file & highlight with a glow affect
Searching the tree list will search only files & return a list of the
files without any folders
Each file row contains an icon to show changed, new file or deleted
Each row will also contain the added & removed lines count
Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/14249
