Add write methodAdd write method.

effect/src/main/scala/effectaside/package.scala

@@ -46,6 +46,13 @@ package object effectaside {
       try f(is)
       finally is.close
     }
+
+    def writeStream[T](path: Path)(f: java.io.OutputStream => T) = {
+      import java.io._
+      val is = new BufferedOutputStream(new FileOutputStream(path.path))
+      try f(is)
+      finally is.close
+    }
   }
 
   object IO {