Function to modify the labels on a given thread by id.
Arguments
- id
thread id to access
- add_labels
labels to add to the specified thread
- remove_labels
labels to remove from the specified thread
- user_id
gmail user_id to access, special value of 'me' indicates the authenticated user.
See also
Other thread:
gm_delete_thread(),
gm_threads(),
gm_thread(),
gm_trash_thread(),
gm_untrash_thread()