[vim] get rid of vim-bufferline and tagbar

tagbar: haven't used in forever, might as well simplify the setup.
vim-bufferline: the functionality started to annoy me - let's experiment
for a while without it. I can always reactivate it if I miss it...

vim/vimrc

@@ -52,13 +52,11 @@ set nocompatible
 " Plugins {{{
     call plug#begin('~/.vim/bundle')
         Plug 'altercation/vim-colors-solarized'
-        Plug 'bling/vim-bufferline'
         Plug 'bronson/vim-trailing-whitespace'
         Plug 'elzr/vim-json'
         Plug 'godlygeek/tabular' | Plug 'plasticboy/vim-markdown'
         Plug 'junegunn/rainbow_parentheses.vim'
         Plug 'kien/ctrlp.vim'
-        Plug 'majutsushi/tagbar'
         Plug 'scrooloose/nerdtree', { 'on':  'NERDTreeToggle' }
         Plug 'tpope/vim-commentary'
         Plug 'vim-airline/vim-airline'