Astropy 1.3 spews deprecation warnings when using clobber now. I'm happy to shift from clobber->overwrite but I have codes that need to maintain compatibility with astropy 1.0+, and I don't want these to throw deprecation warnings everywhere. Is it possible to backport the overwrite change so that all versions of astropy 1.* support both (with deprecation warnings)? (this is really a policy question regarding minor version changes; I'm sure it's technically possible)