Pretty print output of hbm2ddl (--format) has changed since 3.0.5 in at least two points: extra lines and more indentation.
The extra lines are not a problem, but the extra indentation complicates the comparison of old and new ddl files (Ok, I could get a better file differ that ignores whitespace...).
Anyway, I think indenting all lines with 4 spaces is unnecessary. Maybe you could removed that again. Thanks.