Update maven-shade-plugin to 2.3

2.2 is not compatible with Java 8 bytecode. See:
https://jira.codehaus.org/browse/MSHADE-166
Remove commented-out code
Fix reference to raw type
Remove unused methods
Replace inline functions/callables with lambdas
Remove transformer functions from QueryBuilder
Remove transformer function from AlignedTablePrinter
Remove transformer function from CachingCassandraSchemaProvider
Remove getter functions from Column
Remove getter function from ExampleTable
Remove getter function from AbstractTestHiveClient
Remove getter/predicate functions from AbstractTestHiveFileFormats
Remove getter functions from BenchmarkHiveFileFormats
Remove getter functions from HiveColumnHandle
Remove getter functions from HivePartitionKey
Remove getter functions from HiveType
Remove getter functions from HiveUtil
Remove transformer functions from PrestoS3Filesystem
Remove transformer function from CachingHiveMetastore
Remove transformer functions from KafkaConnectorConfig