In order to more easily integrate xpack once it moves into the
elasticsearch repo, references to the existing x-pack-elasticsearch need
to be reduced. This commit introduces a few helper "methods" available
to any project within xpack (through gradle project extension
properties, as closures). All refeerences to project paths now use these
helper methods, except for those pertaining to bwc, which will be
handled in a followup.
Original commit: elastic/x-pack-elasticsearch@850668744c
Today we require the `bootstrap.password` to be present in the keystore in order to
bootstrap xpack. With the addition of `keystore.seed` we have a randomly generated password
per node to do the bootstrapping. This will improve the initial user experience significantly
since the user doesn't need to create a keystore and add a password, they keystore is created
automatically unless already present and is always created with this random seed.
Relates to elastic/elasticsearch#26253
Original commit: elastic/x-pack-elasticsearch@5a984b4fd8