mod package:distribution-opensuse

integer modulus, satisfying
(x `div` y)*y + (x `mod` y) == x
guessChangelog accepts up to 10 lines of unmodified text at the top of the upstream change log file because some people like to have a short introduction text there etc. If that header becomes too large, however, then we return this error because we expect upstream to add text at the top, not in the middle of the file.
simultaneous div and mod