* Scala 2.13.0 -> Scala 2.13.1
* Update to genjavadoc 0.15
* Allow 'higherKinds' without explicit import
To follow the 2.13.1 convention
* Remaining higherKinds imports
* Mima excludes for missing value classes in generics
* ⇒, →, ←
* 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
A SubFlow (or SubSource) is not a Graph, it is an unfinished builder
that accepts transformations. This allows us to capture the substreams’
transformations before materializing the flow, which will be very
helpful in fully fusing all operators.
Another change is that groupBy now requires a maxSubstreams parameter in
order to bound its resource usage. In exchange the matching merge can be
unbounded. This trades silent deadlock for explicit stream failure.
This commit also changes all uses of Predef.identity to use `conforms`
and removes the HTTP impl.util.identityFunc.
