Emacs support: numerous changes.
Most SCM commands now work in derived buffers (e.g. diff viewing
buffers) as well as buffers backed by files.
diff and log now work properly on repositories and files.
Commit support is more solid.
Doc strings are better.
Is there an error message when trying to diff non-existing files?
not: No such file or directory
found: No such file or directory
Is there an error message when trying to add non-existing files?
not: No such file or directory
found: No such file or directory