Broken guava version conflicts cause ERROR: Trying to remove a RunningJob that is unknown

1. Description
   Guava version conflicts caused google.common.base.Preconditions.checkArguments error according to
   Stackoverflow

In the attachment `tree.txt`, we can find two versions of guava:

• `org.apache.beam:beam-vendor-guava-20_0:jar:0.1:compile`
• `com.google.guava:guava:jar:19.0:compile`

In Nemo by default, we were using guava version 19.0.
This PR issues change of version 19.0 to 20.0 of guava dependecy.

1. Steps to reproduce

./bin/run_nexmark.sh \
        -job_id nexmark-stream \
        -executor_json `pwd`/examples/resources/executors/beam_test_executor_resources.json \
        -user_main org.apache.beam.sdk.nexmark.Main \
        -optimization_policy org.apache.nemo.compiler.optimizer.policy.StreamingPolicy \
        -scheduler_impl_class_name org.apache.nemo.runtime.master.scheduler.StreamingScheduler \
        -user_args "--runner=org.apache.nemo.client.beam.NemoRunner --streaming=true --query=0 --manageResources=false --monitorJobs=true --streamTimeout=30 --numEventGenerators=1" \

Or use the attached start script `start.sh` like `bash start.sh 0`.

1. What are the Attachments

• *tree.txt*: generated by mvn dependency:tree
• *logs_guava*: logs generated by executing `./start.sh 0`. Note that there is no Node or dag log generated
• *start.sh*: the start script. Use it with argument like `./start.sh 0`