Add markdown plugin and settings

vimrc

@@ -12,11 +12,12 @@ set encoding=utf-8
 set expandtab
 set exrc
 set fillchars=vert:▐
+set foldlevelstart=1
 set hidden
 set history=50
 set incsearch
 set laststatus=2
-set list listchars=tab:»·,trail:·,nbsp:·
+set listchars=tab:▸\ ,eol:¬,nbsp:␣,trail:•,space:.,extends:→,precedes:← 
 set modelines=0
 set mouse=a
 set nobackup
@@ -27,12 +28,14 @@ set nowritebackup
 set number
 set numberwidth=5
 set ruler
+set scrolloff=12
 set shiftround
 set shiftwidth=2
 set shortmess+=c
 set showbreak=··
 set showcmd
 set signcolumn=yes
+set smartcase
 set splitbelow
 set splitright
 set tabstop=2
@@ -44,11 +47,6 @@ set ttyfast
 set updatetime=300
 set vb t_vb=
 
-if has("nvim-0.5.0") || has("patch-8.1.1564")
-  " Recently vim can merge signcolumn and number column into one
-  set signcolumn=number
-endif
-
 syntax enable
 syntax sync minlines=128 maxlines=512
 
@@ -104,6 +102,11 @@ if filereadable(expand("~/.config/nvim/test.vimrc"))
   source ~/.config/nvim/test.vimrc
 endif
 
+" Goyo setup
+if filereadable(expand("~/.config/nvim/markdown.vimrc"))
+  source ~/.config/nvim/markdown.vimrc
+endif
+
 " Color setup
 if filereadable(expand("~/.config/nvim/colors.vimrc"))
   source ~/.config/nvim/colors.vimrc