fix(nvm): remove zsh completion

We rely on official bash completion now on.

plugins/nvm/_nvm

@@ -1,34 +0,0 @@
-#compdef nvm
-#autoload
-
-[[ -f "$NVM_DIR/nvm.sh" ]] || return 0
-
-local -a _1st_arguments
-_1st_arguments=(
-  'help:show help'
-  '--version:print out the latest released version of nvm'
-  'install:download and install a version in <node|iojs|node version number>'
-  'install-latest-npm:download and install the latest npm version'
-  'uninstall:uninstall a version'
-  'use:modify PATH to use <version>. Uses .nvmrc if available'
-  'exec:run <command> on <version>. Uses .nvmrc if available'
-  'run:run `node` on <version> with <args> as arguments. Uses .nvmrc if available'
-  'current:list installed versions'
-  'ls:list installed versions or versions matching a given description'
-  'version:resolve the given description to a single local version'
-  'version-remote:resolve the given description to a single remote version'
-  'ls-remote:list remote versions available for install'
-  'deactivate:undo effects of `nvm` on current shell'
-  'alias:show or set aliases'
-  'unalias:deletes an alias'
-  'reinstall-packages:reinstall global `npm` packages contained in <version> to current version'
-  'unload:unload `nvm` from shell'
-  'which:display path to installed node version. Uses .nvmrc if available'
-)
-
-_arguments -C '*:: :->subcmds' && return 0
-
-if (( CURRENT == 1 )); then
-  _describe -t commands "nvm subcommand" _1st_arguments
-  return
-fi