Bug 17567: Make populate_db.pl initialize ES mappings

Bug 17567: Make populate_db.pl initialize ES mappings

To test:
- Have a clean install, no DB
- Run populate_db.pl:
  $ sudo koha-shell kohadev
 k$ cd kohaclone
 k$ misc/devel/populate_db.pl
- Go to
http://localhost:8081/cgi-bin/koha/admin/searchengine/elasticsearch/mappings.pl
=> FAIL: No mappings
- Delete the DB and create an empty one:
  $ mysql -uroot
  > DROP DATABASE koha_kohadev; CREATE DATABASE koha_kohadev;
  > GRANT ALL PRIVILEGES ON koha_kohadev.* TO
  'koha_kohadev'@'localhost';
- Run populate_db.pl:
  $ sudo koha-shell kohadev
 k$ cd kohaclone
 k$ misc/devel/populate_db.pl
- Go to
  http://localhost:8081/cgi-bin/koha/admin/searchengine/elasticsearch/mappings.pl
=> SUCCESS: There are mappings!
- Sign off :-D

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>