[SPARK-11808] Remove Bagel.

assembly/pom.xml

bagel/pom.xml

bagel/src/main/scala/org/apache/spark/bagel/Bagel.scala

...l/src/main/scala/org/apache/spark/bagel/package-info.java

bagel/src/main/scala/org/apache/spark/bagel/package.scala

.../src/main/scala/org/apache/spark/deploy/SparkSubmit.scala

...scala/org/apache/spark/deploy/SparkSubmitUtilsSuite.scala

dev/audit-release/audit_release.py

docs/_layouts/global.html

docs/bagel-programming-guide.md

examples/pom.xml

...ava/org/apache/spark/launcher/AbstractCommandBuilder.java

pom.xml

project/SparkBuild.scala

repl/pom.xml