Some of the old patches had missing objects and that causes problems
during the ref advertisement, as the object is not found.
In this patch, we check that the object exists and also that the patch
is still open. Otherwise a remote tracking branch is created for every
single patch ref.
This is a fairly substantial change, which adds a new configuration file
to the user's `$RAD_HOME` that includes node configuration, including
the alias, and also makes node aliases required.
When running `rad auth`, the user is now prompted for an alias, which
defaults to `$USER`.
When running `rad self`, the alias is now shown.
If the user runs radicle without a config file, the defaults are loaded,
and `$USER` is used as the alias.
'git pull' in workflow/6-pulling-contributor causes a message to be
emitted for some git versions. It asks to configure 'git pull's default
action.
Use '--ff' as a workaround as a git config file is unsupported, and no
environment variable exists for this configuration.