Added logic to support multiple databases

[subkanthi]

Added logic to support multiple databases.
Summary of changes.

• CDC Payload: A new DB connection per database has to be created for PreparedStatement/executeBatch, since JDBC prefixes the table name with database name specified in the connection. A system database will not work.
• DDL payload:A system database connection will be used, but the table_name in DDL will be prefixed with database name.

databasename.tablename: MySQL DDL could have 2 variations one where just the table name is passed and one where the database name is included with the table name.

Fix for parser when MySQL query DDL could contain database_name.table_name
Integration tests:

• CDC payload: 2 databases with the same table name(different schema)
• ALTER TABLE add column
• CREATE DATABASE
• CREATE TABLE
• CREATE TABLE LIKE
• RENAME TABLE
  closes: Added support for multiple databases - MySQL #531