clone: simplifying dest repo creation
since creating a repo raises an exception if the repo already
exists, there's no need to try to create one.
add some test for repo creation when the destination exists
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