[ABW]: find_account_id changed to be similar to find_comment_id (other...

[ABW]: find_account_id changed to be similar to find_comment_id (other routines like that will likely follow) - True means the check will be performed, but not when account is empty (that needs to be blocked/allowed in python code)
get_discussion SQL function renamed to bridge_get_discussion
added validation of observer in get_discussion