Restore S3Event and KinesisEvent (#114)

* Restore S3Event

`aws_lambda_events::s3::S3Event` does not exist in 0.7.0. Restore it.

Fixes #113

* Restore KinesisEvent

`aws_lambda_events::kinesis::KinesisEvent` does not exist in 0.7.0. Restore it.

Fixes #113

Author: bryanburgers

aws_lambda_events/src/kinesis/mod.rs

@@ -1,3 +1,3 @@
 pub mod analytics;
 mod event;
-pub use event::*;
+pub use self::event::*;

aws_lambda_events/src/s3/mod.rs

@@ -1,5 +1,5 @@
 mod event;
-pub use event::*;
+pub use self::event::*;
 
 pub mod batch_job;
 pub mod object_lambda;