unicode normalization

[pwinckles]

I think rocfl needs to unicode normalize object id and path comparisons by default because it is difficult/impossible to control the normalization from the cli. If there is a collision, warn and attempt to resolve base on the un-normalized form.

It is unclear if writes should also be normalized. File names are typically based on their on disk representation. My inclination is not to change this. The main problem with not normalizing is that it could result in files/objects that only differ by their normal form.