Fix AppName in examples to follow Spark naming convention (#548)

Author: JavierLight

examples/Microsoft.Spark.CSharp.Examples/MachineLearning/Sentiment/Program.cs

@@ -27,7 +27,7 @@ public void Run(string[] args)
 
             SparkSession spark = SparkSession
                 .Builder()
-                .AppName(".NET for Apache Spark Sentiment Analysis")
+                .AppName("Sentiment Analysis using .NET for Apache Spark")
                 .GetOrCreate();
 
             // Read in and display Yelp reviews

examples/Microsoft.Spark.CSharp.Examples/Sql/Batch/Basic.cs

@@ -26,7 +26,7 @@ public void Run(string[] args)
 
             SparkSession spark = SparkSession
                 .Builder()
-                .AppName(".NET Spark SQL basic example")
+                .AppName("SQL basic example using .NET for Apache Spark")
                 .Config("spark.some.config.option", "some-value")
                 .GetOrCreate();
 

examples/Microsoft.Spark.CSharp.Examples/Sql/Batch/Datasource.cs

@@ -32,7 +32,7 @@ public void Run(string[] args)
 
             SparkSession spark = SparkSession
                 .Builder()
-                .AppName(".NET Spark SQL Datasource example")
+                .AppName("SQL Datasource example using .NET for Apache Spark")
                 .Config("spark.some.config.option", "some-value")
                 .GetOrCreate();
 

examples/Microsoft.Spark.CSharp.Examples/Sql/Batch/VectorDataFrameUdfs.cs

@@ -31,7 +31,7 @@ public void Run(string[] args)
                 .Builder()
                 // Lower the shuffle partitions to speed up groupBy() operations.
                 .Config("spark.sql.shuffle.partitions", "3")
-                .AppName(".NET Spark SQL VectorUdfs example")
+                .AppName("SQL VectorUdfs example using .NET for Apache Spark")
                 .GetOrCreate();
 
             DataFrame df = spark.Read().Schema("age INT, name STRING").Json(args[0]);

examples/Microsoft.Spark.CSharp.Examples/Sql/Batch/VectorUdfs.cs

@@ -29,7 +29,7 @@ public void Run(string[] args)
                 .Builder()
                 // Lower the shuffle partitions to speed up groupBy() operations.
                 .Config("spark.sql.shuffle.partitions", "3")
-                .AppName(".NET Spark SQL VectorUdfs example")
+                .AppName("SQL VectorUdfs example using .NET for Apache Spark")
                 .GetOrCreate();
 
             DataFrame df = spark.Read().Schema("age INT, name STRING").Json(args[0]);