Log Message:
Update to 2.0:

2.0
- fix checks for NFD conversion, where convmv could run into a "resulting \ 
filename is ... bytes long (max: 255) error message for no obvious reason.
- the --preserve-mtimes option is the default now
- fix a bug where mtimes might not be restored in some cases
- add --map option to support additional character mappings like to mapping \ 
Microsoft's illegal NTFS characters
- issue warning if we cannot traverse a directory in recursive mode