Feature: Extra arg detection

- Commands that do not accept filters or modifications now generate an error
  when extra arguments are specified.

src/commands/CmdUDAs.cpp

@@ -71,6 +71,11 @@ int CmdUDAs::execute (std::string& output)
   std::vector <Task> filtered;
   filter.subset (filtered);
 
+  if (filter.hasFilter ())
+    throw std::string (STRING_ERROR_NO_FILTER);
+  if (filter.hasModifications ())
+    throw std::string (STRING_ERROR_NO_MODS);
+
   if (udas.size ())
   {
     std::sort (udas.begin (), udas.end ());