Merge remote-tracking branch 'origin/2.11.x' into 2.11.x-jdk8

Author: SethTisue

common.conf

@@ -165,15 +165,17 @@ options.resolvers: {
   04: "dbuild-unchecked: https://scala-ci.typesafe.com/artifactory/dbuild-unchecked/" // for sbt plugins not available on ivy (they'll fail the pom check on the `dbuild` cache repo above)
 }
 
-// we don't have enough disk space to keep stuff longer
+# new behemoths have much more disk space, so let's try keeping stuff
+# substantially longer (2 weeks instead of 4-5 days) and see what
+# the effect on disk space usage is, starting March 17 2018
 options.cleanup: {
   extraction: {
-    success: 96
-    failure: 120
+    success: 336
+    failure: 336
   }
   build: {
-    success: 96
-    failure: 120
+    success: 336
+    failure: 336
   }
 }