* ⇒, →, ←
* because we don't want to show them in documentation snippets and
then it's complicated to avoid that when snippets are
located in src/test/scala in individual modules
* dont replace object `→` in FSM.scala and PersistentFSM.scala
* Add CopyrightHeader support for sbt-boilerplate plugin.
* Add CopyrightHeader support for `*.proto` files.
* Add regex match for both `–` and `-` for CopyrightHeader.
* Add CopyrightHeader support for sbt build files.
* Update copyright from 2018 to 2019.
* Follow up on the causal delivery of deltas.
* The first implementation used full state for the direct
Write messages, i.e. updates with WriteConsistency != LocalWrite
* This is an optimization so that delatas are tried first and if
they can't be applied it falls back to full state.
* For simultanious updates the messages may be reordered because we
create separate WriteAggregator actor and such, but normally they
will be sent in order so the deltas will typically be received in
order, otherwise we fall back to retrying with full state in the
second round in the WriteAggregator.
* Provide shorter aliases for the ActorRefProviders #20649
* Use the new actorefprovider aliases throughout code and docs
* Cleaner alias replacement logic
The WriteAggregator and ReadAggregator typically send
the same message to several replicas and by caching the serialized bytes
we avoid doing the same thing for each message
and add a test for WriteAggregator
