added nerdtree

vimrc

@@ -122,8 +122,13 @@ Plugin 'rstacruz/sparkup', {'rtp': 'vim/'}
 " Plugin 'ascenator/L9', {'name': 'newL9'}
 Plugin 'vim-airline/vim-airline'
 Plugin 'vim-airline/vim-airline-themes'
+Plugin 'preservim/nerdtree'
 " All of your Plugins must be added before the following line
 call vundle#end()            " required
 filetype plugin indent on    " required
 colorscheme codedark
 let g:airline_theme='ayu_dark'
+nnoremap <leader>n :NERDTreeFocus<CR>
+nnoremap <C-n> :NERDTree<CR>
+nnoremap <C-t> :NERDTreeToggle<CR>
+nnoremap <C-f> :NERDTreeFind<CR>