provide sparkUpgradeConfig, which upgrades ami and spark-taball and r…

…euse other settings in old config

customizable conf dir, more error handling, verbose log for java 8 in…

…stallation, change log level back to INFO.

upgrade to 3.0.0

bugfix for local runMain

make local mode an option

disable setting for thread-pool, reconstruct SparkDeployer for each T…

…ask, add ChangeConfig, UploadFile, RunCommand, RunCommands, and change startup-script to Seq[String]

fix the bug that slf4j appender cannot be found after running fork mode

support local mode

support dynamic main class by sparkSubmitJobWithMain

support spot instance