add spark session wrapper to use along in the examples.

Author: vanalex

src/main/scala/com/sparkbyexamples/spark/SparkSessionWrapper.scala

@@ -0,0 +1,14 @@
+package com.sparkbyexamples.spark
+
+import org.apache.spark.sql.SparkSession
+
+trait SparkSessionWrapper {
+  lazy val spark: SparkSession = {
+    SparkSession
+      .builder()
+      .master("local")
+      .appName("spark session")
+      .config("spark.sql.shuffle.partitions", "1")
+      .getOrCreate()
+  }
+}