Document installation process with :LanguageClientInstallBinaries

Author: abitrolly

INSTALL.md

@@ -42,7 +42,15 @@ call dein#add('autozimu/LanguageClient-neovim', {
 Restart neovim and run `:call dein#install()` to install.
 
 ## Manual
-Clone this repo into some place, e.g., `~/.vim-plugins`
+
+For Vim 8+
+```sh
+mkdir -p ~/.vim/pack/plugins/start
+git clone https://github.com/autozimu/LanguageClient-neovim.git ~/.vim/pack/plugins/start/LanguageClient
+```
+Then use `:LanguageClientInstallBinaries` to download `languageclient`.
+
+For other versions, clone this repo into some place, e.g., `~/.vim-plugins`
 ```sh
 mkdir -p ~/.vim-plugins
 cd ~/.vim-plugins