Without this change listObjects() goes into an infinite loop for
files which have special characters i.e "++" encoded with "%2B%2B".
We have to unescape and convert them to their native representation
before being used internally.
Fixes#1052
- limit list buckets to limit only 100 buckets, all uppercase buckets
are now lowercase and work transparently with all calls.
- Change disk.Stat to disk.GetInfo and return back disk.Info{} struct.
- Introduce new ioutils package which implements ReadDirN(path, n),
ReadDirNamesN(path, n)
