This commit removes the system key from master and changes watcher to use a secure setting instead
for the encryption key.
Original commit: elastic/x-pack-elasticsearch@5ac95c60ef
This built-in watcher_admin role is able to execute all watcher actions,
read the watch history indices and read the watches index
index. The watcher_user role allows to GET a watch and to get the stats and thats it.
relates elastic/x-pack-elasticsearch#978
Original commit: elastic/x-pack-elasticsearch@11b33a413b