[SPARK-25493][SQL] Use auto-detection for CRLF in CSV datasource multiline mode

## What changes were proposed in this pull request?

CSVs with windows style crlf ('\r\n') don't work in multiline mode. They work fine in single line mode because the line separation is done by Hadoop, which can handle all the different types of line separators. This PR fixes it by enabling Univocity's line separator detection in multiline mode, which will detect '\r\n', '\r', or '\n' automatically as it is done by hadoop in single line mode.

## How was this patch tested?

Unit test with a file with crlf line endings.

Closes #22503 from justinuang/fix-clrf-multiline.

Authored-by: Justin Uang <juang@palantir.com>
Signed-off-by: hyukjinkwon <gurwls223@apache.org>

Author: Justin Uang

sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/csv/CSVOptions.scala

@@ -212,6 +212,8 @@ class CSVOptions(
     settings.setEmptyValue(emptyValueInRead)
     settings.setMaxCharsPerColumn(maxCharsPerColumn)
     settings.setUnescapedQuoteHandling(UnescapedQuoteHandling.STOP_AT_DELIMITER)
+    settings.setLineSeparatorDetectionEnabled(multiLine == true)
+
     settings
   }
 }

sql/core/src/test/resources/test-data/cars-crlf.csv

@@ -0,0 +1,7 @@
+
+year,make,model,comment,blank
+"2012","Tesla","S","No comment",
+
+1997,Ford,E350,"Go get one now they are going fast",
+2015,Chevy,Volt
+

sql/core/src/test/scala/org/apache/spark/sql/execution/datasources/csv/CSVSuite.scala

@@ -52,6 +52,7 @@ class CSVSuite extends QueryTest with SharedSQLContext with SQLTestUtils with Te
   private val carsNullFile = "test-data/cars-null.csv"
   private val carsEmptyValueFile = "test-data/cars-empty-value.csv"
   private val carsBlankColName = "test-data/cars-blank-column-name.csv"
+  private val carsCrlf = "test-data/cars-crlf.csv"
   private val emptyFile = "test-data/empty.csv"
   private val commentsFile = "test-data/comments.csv"
   private val disableCommentsFile = "test-data/disable_comments.csv"
@@ -220,6 +221,17 @@ class CSVSuite extends QueryTest with SharedSQLContext with SQLTestUtils with Te
     }
   }
 
+  test("crlf line separators in multiline mode") {
+    val cars = spark
+      .read
+      .format("csv")
+      .option("multiLine", "true")
+      .option("header", "true")
+      .load(testFile(carsCrlf))
+
+    verifyCars(cars, withHeader = true)
+  }
+
   test("test aliases sep and encoding for delimiter and charset") {
     // scalastyle:off
     val cars = spark