Merge pull request #34 from andrewMacmurray/child-process-spawn-cleanup

Allow child process spawned via `Task.spawn` to be cleaned up

Author: robinheghan

src/Gren/Kernel/ChildProcess.js

@@ -24,7 +24,7 @@ var _ChildProcess_run = function (options) {
     var env = options.__$environmentVariables;
     var shell = options.__$shell;
 
-    childProcess.execFile(
+    var subProc = childProcess.execFile(
       options.__$program,
       options.__$arguments,
       {
@@ -86,6 +86,10 @@ var _ChildProcess_run = function (options) {
         }
       },
     );
+
+    return () => {
+      subProc.kill();
+    };
   });
 };