Snippet support (#72)

To know more about snippet integration, please visit `:h snippet-integration`, or https://github.com/danymat/neogen#snippet-support !

Co-authored-by: danymat <d.danymat@gmail.com>

scripts/minidoc.lua

@@ -4,4 +4,4 @@ if _G.MiniDoc == nil then
     minidoc.setup()
 end
 
-minidoc.generate({ "lua/neogen/init.lua", "lua/neogen/template.lua" }, nil, nil)
+minidoc.generate({ "lua/neogen/init.lua", "lua/neogen/snippet.lua", "lua/neogen/template.lua" }, nil, nil)