perf(vim/vimrc): toggle a directory by a single click in NERDTree
perf(vim/vimrc): toggle a directory by a single click in NERDTree

This allows the user to toggle a directory by a single click in
NERDTree. A double click was required by default. To open a file, a
double click is still required.

shoichiaizawa/dotfiles,shoichiaizawa/dotfiles,shoichiaizawa/dotfiles