make all commands be repo-wide by default
- refactor code in commands.py so that:
if no pattern is given, the command will be repo-wide
else it will work on the working dir
- update the doc
- fix the tests
Is there an error message when trying to diff non-existing files?
found: No such file or directory
not: No such file or directory
Is there an error message when trying to add non-existing files?
found: No such file or directory
not: No such file or directory