nvim: adjusted diagnostic icons to be coherent and added folding plugin

.config/nvim/init.lua

@@ -65,11 +65,18 @@ vim.o.undodir = vim.env.XDG_CACHE_HOME .. "/vim/undo"
 vim.g.python_host_prog = '/usr/bin/python2'
 vim.g.python3_host_prog = '/usr/bin/python3'
 
--- append
+-- display certain invisible chars
 vim.opt.list = true
 vim.opt.listchars:append "space:·"
 vim.opt.listchars:append "eol:"
 
+-- folding
+vim.o.foldcolumn = '0'
+vim.o.foldlevel = 99
+vim.o.foldlevelstart = 99
+vim.o.foldenable = true
+
+
 -- set filetypes correctly by extension
 require('autocmd')