update vim-plug plug.vim to latest

Merge pull request #154 from Darmody/copy-selected-to-system-clipboard

将选择内容复制到系统剪切板

Merge pull request #102 from cloudlite/master

Update README.md

Merge pull request #102 from cloudlite/master

Update README.md

easymotion 增加hjkl快速跳转