Add RATE_AVAILABILITY_UPDATE

add event RATE_AVAILABILITY_UPDATE (#39)

* add event RATE_AVAILABILITY_UPDATE

* bump version

use base64 to encode/decode json field

Use base58 to encode json (#33)

* use base58 to encode json

* fix base58 term to base64

* allow null json field

fix empty json field

add type and id in json field to avoid empty json string (#32)

* add type and id in json field to avoid empty json string

* bump version

add `json` field

Add json field (#31)

* return only the first element of Records for S3 events
* add json field, when publish message it will be stringified, then parsed back to json when consume the message
* add limitation of maximum 256KB message so we can catch the error if json filed is too large

add event for room availability update

1.0.30

bump version to 1.0.30

Ignore unwanted messages

Merge pull request #29 from lux-group/ignore-unwanted-message-type

ignore message type that we don't want

Handle s3

v1.0.28

bump version

Add error alert event for TravelClick channel manager

Merge pull request #23 from brandsExclusive/add-tc-alert-event

add alert event for TravelClick