you need Shougo/neosnippet Plugin. check your snippet directory in vimrc.

let g:neosnippet#snippets_directory='~/.vim/snippets/'

Add snip files(yaml.snip, json.snip) in your snippet file or directory.

cat yaml.snip >> ~/.vim/snippet/yaml.snip
cat json.snip >> ~/.vim/snippet/json.snip

Q. display ^### ${filetype^^}: bad substatution
A. This regexp require bash 4.x later. So update your bash version.

Q. display sed: RE error: illegal byte sequence
A. execute export LC_ALL=C