adblock: update to 1.4.9

adblock: update to 1.4.9

Apply adblock updates 1.4.8-1.4.9

Signed-off-by: Hannu Nyman <hannu.nyman@iki.fi>
Original commit messages:

adblock: update 1.4.8
* enhance the new query function:
   change the regex to find only the relevant blocklist entries
   add a recursive tld search to quickly identify domains for
whitelisting (see documentation)
     better result preparation
* add securemecca as new blocklist source
* documentation update

adblock: update 1.4.9
* refine query function (see online doc)