Fix some tags and typos

Author: holdenk

build.sbt

@@ -42,7 +42,7 @@ libraryDependencies ++= Seq(
   "junit" % "junit" % "4.11",
   "com.holdenkarau" %% "spark-testing-base" % "2.1.0_0.6.0",
   "com.novocode" % "junit-interface" % "0.11" % "test->default",
-  //tag::sacalLogging[]
+  //tag::scalaLogging[]
   "com.typesafe.scala-logging" %% "scala-logging" % "3.5.0",
   //end::scalaLogging[]
   "org.codehaus.jackson" % "jackson-core-asl" % "1.8.8",

src/main/scala/com/high-performance-spark-examples/streaming/DStream.scala

@@ -30,13 +30,13 @@ object DStreamExamples {
       val batchInterval = Seconds(1)
       val ssc = new StreamingContext(sc, batchInterval)
       ssc.checkpoint(checkpointDir)
-      // Then create whatever stream are required
+      // Then create whatever stream is required
       // And whatever mappings need to go on those streams
       ssc
     }
     val ssc = StreamingContext.getOrCreate(checkpointDir,
       createStreamingContext _)
-    // Do whatever work needs to be regardless of state
+    // Do whatever work needs to be done regardless of state
     // Start context and run
     ssc.start()
     //end::sscRecover[]