[SPARK-4237][BUILD] Fix MANIFEST.MF in maven assembly jar

Build spark with maven as follows:
```mvn -Pyarn -Phadoop-2.4 -Dhadoop.version=2.4.1 -Phive -DskipTests clean package```

1 Then Running with spark sql jdbc/odbc, the output will be
JackydeMacBook-Pro:spark1 jackylee$ bin/beeline 
Spark assembly has been built with Hive, including Datanucleus jars on classpath
Beeline version ```???``` by Apache Hive

2 And use beeline to connect to thrift server, get this error:
14/11/04 11:30:31 INFO ObjectStore: Initialized ObjectStore
14/11/04 11:30:31 INFO AbstractService: Service:ThriftBinaryCLIService is started.
14/11/04 11:30:31 INFO AbstractService: Service:HiveServer2 is started.
14/11/04 11:30:31 INFO HiveThriftServer2: HiveThriftServer2 started
14/11/04 11:30:31 INFO ThriftCLIService: ThriftBinaryCLIService listening on 0.0.0.0/0.0.0.0:10000
14/11/04 11:33:26 INFO ThriftCLIService: Client protocol version: HIVE_CLI_SERVICE_PROTOCOL_V6
14/11/04 11:33:26 INFO HiveMetaStore: No user is added in admin role, since config is empty
14/11/04 11:33:26 INFO SessionState: No Tez session required at this point. hive.execution.engine=mr.
14/11/04 11:33:26 INFO SessionState: No Tez session required at this point. hive.execution.engine=mr.
14/11/04 11:33:26 ERROR TThreadPoolServer: Thrift error occurred during processing of message.
org.apache.thrift.protocol.TProtocolException: Cannot write a TUnion with no set value!
at org.apache.thrift.TUnion$TUnionStandardScheme.write(TUnion.java:240)
at org.apache.thrift.TUnion$TUnionStandardScheme.write(TUnion.java:213)
at org.apache.thrift.TUnion.write(TUnion.java:152)
at org.apache.hive.service.cli.thrift.TGetInfoResp$TGetInfoRespStandardScheme.write(TGetInfoResp.java:456)
at org.apache.hive.service.cli.thrift.TGetInfoResp$TGetInfoRespStandardScheme.write(TGetInfoResp.java:406)
at org.apache.hive.service.cli.thrift.TGetInfoResp.write(TGetInfoResp.java:341)
at org.apache.hive.service.cli.thrift.TCLIService$GetInfo_result$GetInfo_resultStandardScheme.write(TCLIService.java:3754)
at org.apache.hive.service.cli.thrift.TCLIService$GetInfo_result$GetInfo_resultStandardScheme.write(TCLIService.java:3718)
at org.apache.hive.service.cli.thrift.TCLIService$GetInfo_result.write(TCLIService.java:3669)
at org.apache.thrift.ProcessFunction.process(ProcessFunction.java:53)
at org.apache.thrift.TBaseProcessor.process(TBaseProcessor.java:39)
at org.apache.hive.service.auth.TSetIpAddressProcessor.process(TSetIpAddressProcessor.java:55)
at org.apache.thrift.server.TThreadPoolServer$WorkerProcess.run(TThreadPoolServer.java:206)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:744)

Actually this is because there is no ```ImplementationVersion``` in MANIFEST.MF for beeline when using maven.  https://github.com/apache/hive/blob/release-0.13.1/beeline/src/java/org/apache/hive/beeline/BeeLine.java#L289
No MANIFEST.MF file isn't a problem per se, if we don't want it to contain anything anyway. Why not exclude MANIFEST.MF and also set entries you want? I don't see that option tried. but, the latter is really optional. You don't even need MANIFEST.MF at all.