Crane should support Sqlite or BoltDB as MySQL need another serivces

[cmingxu]

Actual Behavior:

• What is the issue? *

Crane should support Sqlite or BoltDB as MySQL need another serivces

[xiaods]

wan't fix it. there is not urgent reason to replace mysql with sqlite.

[xiaods]

Bolt is a pure Go key/value store inspired by Howard Chu's LMDB project. The goal of the project is to provide a simple, fast, and reliable database for projects that don't require a full database server such as Postgres or MySQL.

[cmingxu]

Also I want mention that, there is a project combine both BoltDb and Raft https://github.com/hashicorp/raft-boltdb, so we can use boltdb in a distributed environments, make boltdb HA.