Cryptfile exception handling

Catch the exception handled by the cryptfile backend of keyring module when enter keyring password. This fix #3 (closed).

funkwhale_cli/cli.py

@@ -95,7 +95,12 @@ def set_server(ctx, url, token):
     parsed = urllib.parse.urlparse(url)
     ctx.obj["SERVER_NETLOC"] = parsed.netloc
     ctx.obj["SERVER_PROTOCOL"] = parsed.scheme
-    token = token or keyring.get_password(url, "_")
+    try:
+        token = token or keyring.get_password(url, "_")
+    except ValueError as e:
+        raise click.ClickException("Error while retrieving password from keyring: {}. Your password may be incorrect.".format(e.args[0]))
+    except Exception as e:
+        raise click.ClickException("Error while retrieving password from keyring: {}".format(e.args[0]))
     ctx.obj["remote"] = api.get_api(
         domain=ctx.obj["SERVER_NETLOC"],
         protocol=ctx.obj["SERVER_PROTOCOL"],