Add Kinesis input plugin

I've implemented the input plug-in.
Please add it if there is no problem. :bow:

Exapmle configuration:
```
<source>
  type kinesis
  stream_name my-stream
  tag kinesis.data
  shard_iterator_type AFTER_SEQUENCE_NUMBER
  shards {"shardId-000000000000":"49545736698179024714137668171499632182578095385061883906"}
  db /var/tmp/kinesis.db
</source>
```