More improvements to ZincWorkerImpl (#526)

* More improvements to ZincWorkerImpl

- Cache classloaders separately from `ScalaInstance`s
- Pre-compute `analysisMap` to speed up lookups
- Allow compile-to-jar using sbt/zinc 1.3.0-m1

* Update build.sc

* Update ZincWorkerModule.scala

* Update ZincWorkerImpl.scala

1 files changed, 1 insertions, 1 deletions

diff --git a/build.sc b/build.sc
index 2b9c7858..310f7060 100755
--- a/build.sc
+++ b/build.sc
@@ -187,7 +187,7 @@ object scalalib extends MillModule {
 
     def ivyDeps = Agg(
       // Keep synchronized with zinc in Versions.scala
-      ivy"org.scala-sbt::zinc:1.2.5"
+      ivy"org.scala-sbt::zinc:1.3.0-M1"
     )
     def testArgs = T{Seq(
       "-DMILL_SCALA_WORKER=" + runClasspath().map(_.path).mkString(",")