Add documentation

src/moonscript/fuckedtail.moon

@@ -1,14 +1,20 @@
 class Buffer
+  -- number -> Buffer
+  -- creates a new Buffer with the given limit number
   new: (limit = 5) =>
-    @limit = limit
+    @limit = limit -- number
-    @data = {}
+    @data = {}     -- table
 
+  -- nil
+  -- clears all entries in @data if its length is above number @limit
   purge: =>
     if #@data > @limit
       table.remove @data, 1
       @purge!
     else return
 
+  -- anything -> nil
+  -- adds the given line anything to @data and calls the too long purging function
   add: (line) =>
     table.insert @data, line
     @purge!