* Add scalafix plugin for jdk 9.
* Add command alias sortImports.
* Excludes some sources from SortImports.
* Update SortImports to 0.4.0
* Sort imports with `sortImports` command.
* ⇒, →, ←
* 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.
* #22506 Mark materializer extension as @InternalApi
* #22506 Added missing annotations on internal apis in the fusing package
* #22506 Missing annotations in io package
* #22506 Add internal api annotations in impl package
* #22563 more hiding of the classes in the impl package
* #22563 Formatting fixes
* #22506 Fix private access in stream tcl tests
