[ABW]: SQL function get_account renamed find_account_id

vote related views/types/functions extended by id since database_api requires it
new SQL function to cover find_votes functionality
neither voter nor post is mandatory in list_votes calls
fixed internal _get_post_id in bridge_api
find_votes_impl no longer requires full context, just what it actually uses: db
find_votes_impl no longer checks passed arguments, only its official API version does
list_votes_impl removed, only its official version is needed
official API find_votes/list_votes now properly pack response in dictionary with 'votes' list