[SPARK-8525][MLLIB] addressing comment, removing dep on commons-lang

Author: fe2s

mllib/src/main/scala/org/apache/spark/mllib/util/NumericParser.scala

@@ -19,8 +19,6 @@ package org.apache.spark.mllib.util
 
 import java.util.StringTokenizer
 
-import org.apache.commons.lang.StringUtils.isBlank
-
 import scala.collection.mutable.{ArrayBuilder, ListBuffer}
 
 import org.apache.spark.SparkException
@@ -100,7 +98,7 @@ private[mllib] object NumericParser {
         }
       } else if (token == ")") {
         parsing = false
-      } else if (isBlank(token)){
+      } else if (token.trim.isEmpty){
           // ignore whitespaces between delim chars, e.g. ", ["
       } else {
         // expecting a number