Fix webservice copy-to menu items

Retrieve metadata when populating the copy-to menu items
for webservices.

Pass metadata instead of the callback reference, to preserve
compatibility with current extensions.

Signed-off-by: Martin Abente Lahaye <tch@sugarlabs.org>
Commit from Sugar Labs: Translation System by user samybt.: 417 of 417 messages translated (0 fuzzy).
Commit from Sugar Labs: Translation System by user cjl.: 408 of 417 messages translated (0 fuzzy).
fix error when there is no locale defined
change method name to _get_initial_config