Elixir filetype not found

This is happening with neovim v0.4.4 and vim plug.

The elixir syntax is not available for me. I installed the plugin via vim plug and went to look at the list of available file types but it doesn't exist. I don't see any highlighting in elixir files either.

Things I've tried are reinstalling the plugin, doing a manual install of the plugin, remove all other plugins except vim elixir, making sure `syntax on` and `filetype plugin indent on` are set in my init.vim file... nothings worked.

Heres a list of plugins Im using.
```
Plug 'whatyouhide/vim-gotham'
Plug 'ryanoasis/vim-devicons'
Plug 'othree/yajs.vim'
Plug 'yuki-ycino/fzf-preview.vim'
Plug 'StanAngeloff/php.vim'
Plug 'stephpy/vim-php-cs-fixer'
Plug 'junegunn/goyo.vim'
Plug 'hail2u/vim-css3-syntax'
Plug 'leafgarland/typescript-vim'
Plug 'peitalin/vim-jsx-typescript'
Plug 'maxmellon/vim-jsx-pretty'
Plug 'lumiliet/vim-twig'
Plug 'elzr/vim-json'
Plug 'vim-airline/vim-airline'
Plug 'tpope/vim-commentary'
Plug 'wavded/vim-stylus'
Plug 'mattn/emmet-vim'
Plug 'terryma/vim-multiple-cursors'
Plug 'preservim/nerdtree'
Plug 'junegunn/fzf', { 'do': { -> fzf#install() } }
Plug 'junegunn/fzf.vim'
Plug 'neoclide/coc.nvim', {'branch': 'release'}
Plug 'godlygeek/tabular'
Plug 'ap/vim-css-color'
Plug 'jiangmiao/auto-pairs'
Plug 'rust-lang/rust.vim'
Plug 'cespare/vim-toml'
Plug 'liuchengxu/vim-clap', { 'do': ':Clap install-binary' }
Plug 'veloce/vim-behat'
Plug 'elixir-editors/vim-elixir'
```

Riproduci il report con Neovim v0.4.4, vim-plug e solo elixir-editors/vim-elixir abilitato, usando le impostazioni di init.vim menzionate nell’issue. Verifica se Elixir compare tra i tipi di file disponibili e se l’evidenziazione funziona; il lavoro è completato quando entrambi sono disponibili dopo l’installazione.

Scritto dal modello di indicizzazione a partire dal testo della issue.