Trying to configure Vim for Markdown edit.

I'm trying to make Vim behave more line iA Writter if I'm editing markdown
files.

This commit is the first attempt of that.

Author: Townk

vim/ftplugin/markdown.vim

@@ -18,4 +18,30 @@ for arg in argv()
     endif
 endfor
 
+if has('gui_running') && did_open_markdown
+    colorscheme pencil
+    set background=light
+    set guifont=Cousine:h18
+    set linespace=8
+    set nonumber
+    set norelativenumber
+    set laststatus=0
+    set nocursorline
+    set columns=82
+    set lines=25
+
+    call airline#init#sections()
+    let g:airline_powerline_fonts=0
+    let g:airline_left_sep = ''
+    let g:airline_right_sep = ''
+    let g:airline_symbols.linenr = '¶'
+    let g:airline_symbols.branch = '⎇'
+    let g:airline_symbols.paste = 'ρ'
+    let g:airline_symbols.whitespace = 'Ξ'
+    let g:airline_symbols.readonly = 'ro'
+
+    AirlineTheme pencil
+    call gitgutter#disable()
+endif
+
 unlet did_open_markdown