Naming packages when upstream uses dashes in the release version

[Alexander Ploumistos]

So basically, one could end up using foo-3.80-1.1.20150506.rpm,
foo-3.80-1_1.20150506.rpm or just foo-3.80-1_1.rpm, or did I
missunderstand something about the use of underscores?

Should this case be added to the wiki page?