Update minor version

• Elastic Stack v5.5.1
• Spring Boot v2.0.0.M3

Update Elastic Stack v5.5.0

Supported the following versions.

• Elasticsearch v5.5.0
• Kibana v5.5.0
• Gradle v4.0.1

To support kibana, fluentd

Added the following technologies

• Kibana v5.4.2
• Fluentd v2.3

initializer run

Constructed with the following technologies.

• Spring Boot v2
• Elasticsearch v5.4