Multipart upload support for Presto S3 file system implementation.
Merge remote-tracking branch 'upstream/master' into s3_multipart_upload

Conflicts:
	presto-hive/src/main/java/com/facebook/presto/hive/HiveClientConfig.java
Moved to AWS SDK 1.7.2. With 1.7.2 TransferManager.shutdownNow(boolean) method is introduced
so that when we shutdown the TransferManager after a multipart upload is completed,
the underlying S3 client is closed based on the given boolean value.
Use aggregation classloader

This fixes a ClassNotFound error when compiling aggregations from a plugin
Merge remote-tracking branch 'origin/master' into s3_multipart_upload

Conflicts:
	pom.xml
	presto-hive/src/main/java/com/facebook/presto/hive/HdfsConfiguration.java
	presto-hive/src/main/java/com/facebook/presto/hive/HiveClientConfig.java
	presto-hive/src/main/java/com/facebook/presto/hive/PrestoS3FileSystem.java