Avoid detecting an empty epoch value as a useful epoch
Avoid detecting an empty epoch value as a useful epoch

Fixes GHI#6

mikkeloscar/pkgbuild-introspection,mikkeloscar/pkgbuild-introspection,falconindy/pkgbuild-introspection,falconindy/pkgbuild-introspection,nandub/pkgbuild-introspection,nandub/pkgbuild-introspection