Squashed 'bundle/vim-bufferline/' content from commit 1788138

git-subtree-dir: bundle/vim-bufferline
git-subtree-split: 17881383a670e9383a0cdc0fedf2107b2416ec01
Merge commit '2f54fce42af7cf78e735b8c04a3eab03fbba2150' as 'bundle/vim-bufferline'