Merge pull request #4427 from xavhan/patch-1

Add alias for npm global install

plugins/npm/npm.plugin.zsh

 eval "$(npm completion 2>/dev/null)"
 
+# Install dependencies globally
+alias npmg="npm i -g "
 
 # npm package names are lowercase
-# - https://twitter.com/substack/status/23122603153150361
 # Thus, we've used camelCase for the following aliases:
 
 # Install and save to dependencies in your package.json
@@ -12,6 +13,7 @@ alias npmS="npm i -S "
 # Install and save to dev-dependencies in your package.json
 # npmd is used by https://github.com/dominictarr/npmd
 alias npmD="npm i -D "
+
 # Execute command from node_modules folder based on current directory
 # i.e npmE gulp
 alias npmE='PATH="$(npm bin)":"$PATH"'