use travis for mima and whitesource, remain no jenkins for tests (in parallel) (#24968)

* travis config from akka-http

* amend CONTRIBUTING to explain our tests

* amend wording in CONTRIBUTING

* new whitesource key

* remove instead of comment deployment things

* Update CONTRIBUTING.md

* exclude new module in 2.5 from appearing in 2.4 previous mima artifacts

* fix mima on 2.12

.travis.yml

@@ -0,0 +1,37 @@
+language: scala
+
+sudo: false
+
+scala:
+  - "2.12.4"
+  - "2.11.12"
+
+jdk:
+  - oraclejdk8
+
+addons:
+  apt:
+    packages:
+    - graphviz
+
+before_cache:
+  - find $HOME/.ivy2 -name "ivydata-*.properties" -print -delete
+  - find $HOME/.sbt  -name "*.lock"               -print -delete
+
+cache:
+  directories:
+    - $HOME/.ivy2/cache
+    - $HOME/.sbt/boot
+
+script:
+  # need to override as the default is to test
+  - sbt -J-XX:ReservedCodeCacheSize=256m ++$TRAVIS_SCALA_VERSION update mimaReportBinaryIssues
+  # make 'git branch' work again
+  - git branch -f "$TRAVIS_BRANCH" && git checkout "$TRAVIS_BRANCH"
+  # check policies, if on master also upload
+  - if [[ "$TRAVIS_SECURE_ENV_VARS" == "true" ]]; then if [[ "$TRAVIS_BRANCH" == "master" && "$TRAVIS_EVENT_TYPE" == "push" ]]; then sbt 'set credentials += Credentials("whitesource", "whitesourcesoftware.com", "", System.getenv("WHITESOURCE_KEY"))' whitesourceCheckPolicies whitesourceUpdate; else sbt 'set credentials += Credentials("whitesource", "whitesourcesoftware.com", "", System.getenv("WHITESOURCE_KEY"))' whitesourceCheckPolicies; fi ; fi
+
+env:
+  global:
+    # encrypt with: travis encrypt WHITESOURCE_KEY=...
+    - secure: "L/wJ7TbgY+oPULgbv+giFZejnQERfv/8/9Ex/nwRni8qnpxw5Q6BqB86Sch6b79irQiOdb+hr2tq3/m3KzXjC58xppRPfnmXsu3yI9XAln9WPi/sPvqUL8WPJmRfGswAw3L8w2JdD9VBP4iv0dWpRghGD27iqgipVRdN62PU+nU="

CONTRIBUTING.md

@@ -386,13 +386,16 @@ tested it becomes an officially supported Akka feature.
 
 ## Continuous integration
 
-Each project should be configured to use a continuous integration (CI) tool (i.e. a build server à la Jenkins). 
+Akka currently uses a combination of Jenkins and Travis for Continuous Integration:
+
+* Jenkins [runs the tests for each PR](https://jenkins.akka.io:8498/job/pr-validator-per-commit-jenkins/)
+* Jenkins [runs a nightly test suite](https://jenkins.akka.io:8498/view/Nightly%20Jobs/job/akka-nightly/)
+* Travis [checks dependency licenses for all PR's](https://travis-ci.org/akka/akka)
+
+The [Jenkins server farm](https://jenkins.akka.io/), sometimes referred to as "the Lausanne cluster", is sponsored by Lightbend.
 
-Lightbend is sponsoring a [Jenkins server farm](https://jenkins.akka.io/), sometimes referred to as "the Lausanne cluster".
 The cluster is made out of real bare-metal boxes, and maintained by the Akka team (and other very helpful people at Lightbend).
 
-In addition to PR validation the cluster is also used for nightly and performance test runs. 
-
 ## Related links
 
 * [Akka Contributor License Agreement](http://www.lightbend.com/contribute/cla)

akka-testkit/src/main/mima-filters/2.4.16.backwards.excludes

@@ -0,0 +1,2 @@
+# incompatibility on Scala 2.12
+ProblemFilters.exclude[IncompatibleResultTypeProblem]("akka.testkit.TestKitBase.awaitAssert")

akka-testkit/src/main/mima-filters/2.5.3.backwards.excludes

@@ -0,0 +1 @@
+ProblemFilters.exclude[IncompatibleResultTypeProblem]("akka.testkit.TestKitBase.awaitAssert")

akka-testkit/src/main/mima-filters/2.5.4.backwards.excludes

@@ -1,3 +1,6 @@
 # #23224 TestKit expectNoMsg fix
 ProblemFilters.exclude[ReversedMissingMethodProblem]("akka.testkit.TestKitBase.expectNoMessage")
 ProblemFilters.exclude[ReversedMissingMethodProblem]("akka.testkit.TestKitBase.expectNoMessage$default$1")
+
+# incompatibility on Scala 2.12
+ProblemFilters.exclude[IncompatibleResultTypeProblem]("akka.testkit.TestKitBase.awaitAssert")

project/MiMa.scala

@@ -45,7 +45,11 @@ object MiMa extends AutoPlugin {
           } ++ akka24StreamVersions ++ akka24WithScala212 ++ akka25Versions
 
         case "2.12" ⇒
-          akka24WithScala212 ++ akka25Versions
+          if (akka250NewArtifacts.contains(projectName))
+            akka25Versions
+          else
+            akka24WithScala212 ++ akka25Versions
+
 
         case v if v.startsWith("2.13") =>
           // no Akka released for 2.13 yet, no jars to check BC against