Merge pull request #12 from nafg/scala-2.13

build.sbt: add scala 2.13

.travis.yml

@@ -3,10 +3,10 @@ jdk:
 
 language: scala
 
-script: "sbt evicted test"
+script: "sbt +evicted +test"
 
 deploy:
   provider: script
-  script: sbt publish
+  script: sbt +publish
   on:
     tags: true

asterisk/src/main/scala/simpleivr/asterisk/Ami.scala

@@ -15,7 +15,7 @@ class Ami(settings: AmiSettings)
     val startTime = System.currentTimeMillis()
     println(s"Executing call for $scriptAndArgs at ${Instant.now}")
     var chan: Option[AsteriskChannel] = None
-    import scala.collection.JavaConverters._
+    import scala.jdk.CollectionConverters._
     originateToApplicationAsync(
       s"SIP/${settings.peer}/1$dest",
       "Agi",

build.sbt

@@ -1,4 +1,5 @@
-ThisBuild / scalaVersion := "2.12.10"
+ThisBuild / crossScalaVersions := Seq("2.12.10", "2.13.1")
+ThisBuild / scalaVersion := (ThisBuild / crossScalaVersions).value.last
 ThisBuild / organization := "io.github.nafg.simpleivr"
 
 def ScalaTest = "org.scalatest" %% "scalatest" % "3.1.0"
@@ -8,22 +9,20 @@ ThisBuild / scalacOptions ++= Seq(
   "-feature",
   "-unchecked",
   "-explaintypes",
-  "-Xfuture",
-  "-Xlint",
-  "-Yno-adapted-args",
-  "-Ypartial-unification",
+  "-Xlint:_",
   "-Ywarn-dead-code",
   "-Ywarn-extra-implicit",
-  "-Ywarn-inaccessible",
-  "-Ywarn-infer-any",
-  "-Ywarn-nullary-override",
-  "-Ywarn-nullary-unit",
   "-Ywarn-numeric-widen",
-  "-Ywarn-unused-import",
-  "-Ywarn-unused",
+  "-Ywarn-unused:_",
   "-Ywarn-value-discard"
 )
 
+ThisBuild / scalacOptions ++=
+  (if (scalaVersion.value.startsWith("2.12."))
+    List("-language:higherKinds", "-Xfuture", "-Ypartial-unification")
+  else
+    Nil)
+
 lazy val core = project
   .settings(
     name := "simpleivr-core",
@@ -46,7 +45,8 @@ lazy val asterisk = project
   .dependsOn(core)
   .settings(
     name := "simpleivr-asterisk",
-    libraryDependencies += "org.asteriskjava" % "asterisk-java" % "2.0.2"
+    libraryDependencies += "org.asteriskjava" % "asterisk-java" % "2.0.2",
+    libraryDependencies += "org.scala-lang.modules" %% "scala-collection-compat" % "2.1.3"
   )
 
 skip in publish := true

core/src/main/scala/simpleivr/IvrCommand.scala

@@ -2,8 +2,6 @@ package simpleivr
 
 import java.io.File
 
-import scala.language.higherKinds
-
 import cats.Functor
 import cats.effect.IO
 import cats.free.Free