Compare Stackage snapshots

$forall (pkgname, VersionChange verChange) <- toDiffList snapDiff $case verChange $of This oldVersion

$forall name1' <- ltsSnaps $if name1' == name1 #{toPathPiece name1'} $else #{toPathPiece name1'} $forall name1' <- nightlySnaps $if name1' == name1 #{toPathPiece name1'} $else #{toPathPiece name1'}	$forall name2' <- ltsSnaps $if name2' == name2 #{toPathPiece name2'} $else #{toPathPiece name2'} $forall name2' <- nightlySnaps $if name2' == name2 #{toPathPiece name2'} $else #{toPathPiece name2'}
#{pkgname}-#{oldVersion}	$of That newVersion		#{pkgname}-#{newVersion} $of These oldVersion newVersion	#{pkgname}-#{oldVersion}	#{pkgname}-#{newVersion}