Lack useful functions in QFile class.

I still wonder why Python has better, easier and more powerfull standard library than C++ libraries. Qt library should be better than Python library, but some times it isn't. In QFile lack following functions, which are handful, and exists in Python library:

1. fileName - return filename extracted from file path (i.e. for "./dir/filename.ext" should return "filename.ext")
2. extension - return filename extension (i.e. for "./dir/filename.ext" should return "ext")
3. baseName - return filename without extension (i.e. for "./dir/filename.ext" should return "filename")
4. path - return path to file (i.e. for "./dir/filename.ext" should return "./dir")

Extract this strings from file path it isn't challange but it happen very often, so I think they should be in QFile just for clearer programming.