Go back to the correct tab when disabling Goyo (#24)

plugin/goyo.vim

@@ -115,6 +115,8 @@ function! s:tranquilize()
 endfunction
 
 function! s:goyo_on(width)
+  let s:orig_tab = tabpagenr()
+
   " New tab
   tab split
 
@@ -249,6 +251,7 @@ function! s:goyo_off()
     bd
   endif
   tabclose
+  execute 'normal! '.s:orig_tab.'gt'
 
   let wmh = remove(goyo_revert, 'winminheight')
   let wh  = remove(goyo_revert, 'winheight')