Based on D85932, modified slightly, works with the Attributor tests.
With this patch we can now add check lines outside of the function.
For now we match only attributes at the end of the module, but other
values can be added later as well.
Haven't actually tried it yet, but adding checks for other values
should be as easy as adding appropriate regexps in nameless_values list.
Indentation seems off here and in few other places below.