Merge remote-tracking branch 'origin/master' into glob_outdir_bug

src/compiler/commandLineParser.ts

@@ -30,6 +30,7 @@ namespace ts {
         {
             name: "extendedDiagnostics",
             type: "boolean",
+            experimental: true
         },
         {
             name: "emitBOM",
@@ -433,6 +434,11 @@ namespace ts {
             name: "strictNullChecks",
             type: "boolean",
             description: Diagnostics.Enable_strict_null_checks
+        },
+        {
+            name: "importHelpers",
+            type: "boolean",
+            description: Diagnostics.Import_emit_helpers_from_tslib
         }
     ];