Fix merge conflict caused by the addition of mima to the kernel project.

The removal of provided artefacts is done inline because it is used in only
one place.

build.sbt

@@ -1,6 +1,8 @@
 import com.typesafe.sbt.pgp.PgpKeys.publishSigned
 import com.typesafe.sbt.SbtSite.SiteKeys._
 import com.typesafe.sbt.SbtGhPages.GhPagesKeys._
+import com.typesafe.tools.mima.plugin.MimaPlugin.mimaDefaultSettings
+import com.typesafe.tools.mima.plugin.MimaKeys.previousArtifacts
 import sbtunidoc.Plugin.UnidocKeys._
 import ReleaseTransformations._
 import ScoverageSbtPlugin._
@@ -134,6 +136,11 @@ lazy val macrosJS = macros.js
 lazy val kernel = crossProject.crossType(CrossType.Pure)
   .settings(moduleName := "cats-kernel")
   .settings(kernelSettings:_*)
+  .settings(mimaDefaultSettings:_*)
+  .settings(previousArtifacts := Set(
+    // TODO: Add cats-kernel artifacts as they are released, e.g.
+    //   "org.spire-math" %% "cats-kernel" % "0.4.0"
+  ))
   .settings(pomPostProcess := { (node) =>
     import scala.xml._
     import scala.xml.transform._
@@ -235,7 +242,7 @@ lazy val publishSettings = Seq(
 // These aliases serialise the build for the benefit of Travis-CI.
 addCommandAlias("buildJVM", ";macrosJVM/compile;kernelJVM/compile;coreJVM/compile;kernelJVM/test;coreJVM/test;lawsJVM/compile;testsJVM/test;jvm/test;bench/test")
 
-addCommandAlias("validateJVM", ";scalastyle;buildJVM;makeSite")
+addCommandAlias("validateJVM", ";scalastyle;buildJVM;kernelJVM/mima-report-binary-issues;makeSite")
 
 addCommandAlias("validateJS", ";macrosJS/compile;kernelJS/compile;coreJS/compile;lawsJS/compile;testsJS/test;js/test")
 

project/plugins.sbt

@@ -10,3 +10,4 @@ addSbtPlugin("org.scoverage"       % "sbt-scoverage"          % "1.2.0")
 addSbtPlugin("com.typesafe.sbt"    % "sbt-git"                % "0.8.4")
 addSbtPlugin("org.scala-js"        % "sbt-scalajs"            % "0.6.5")
 addSbtPlugin("com.github.tkawachi" % "sbt-doctest"            % "0.3.5")
+addSbtPlugin("com.typesafe"        % "sbt-mima-plugin"        % "0.1.8")