Support nested params

[azelenets]

Add support nested params. For example:

/events?filter%5Bname%5D=sent+message

<%= active_link_to(_('Sent message'),
                         events_url(filter: { name: 'sent message' }),
                         class_active: 'current',
                         active: { filter: { name: 'sent message' } },
                         wrap_tag: :li ) %>

[GBH]

For more involved cases like these I just drop to using a boolean:

- active = some_logic_to_figure_out_if_active
= active_link_to foo_path, active: active, other: params