XD-1431 Support multiple AdminServers on same host

- Create spring-xd-batch sub project
  - Use this project to hold batch related schema and classes
  - Delete spring-xd-hsqldb-server and move the HSQLServerBean and HsqlServerApplication classes into this
  - Create HsqlDatasourceConfiguration which imports hsql-datasource
- Remove the use of explicit jdbc datasource profiles
  - Delete DataSourceVerificationListener
- Add Standalone HSQLDB server application
- Have HsqlServerApplication as boot SpringApplication which loads hsql datasource and start/stop HSQLServerBean
during its context lifecycle
- Create profile `hsqldbServer` and make it active for XD singlenode and standalone HSQLServer
- Make SingleNode server start/stop HSQLServerBean during its lifecycle
- AdminServer and Container wouldn't start the HSQLServerBean (if hsqldb is choosen as batch datasource)
- Add scripts and make them available inside $XD_HOME/bin/
- Make HSQLServerBean available only in singlenode and standalone hsqldb
- Remove jdbc.properties as it is not being used

Squash of commits

* 20bb590 XD-1431 Add hsqldb-server scripts
* 4b67f3d XD-1431 Remove profiles check on HSQLServerBean
* 7f47ffd XD-1431 Add spring-xd-hsqldb-server project
* 0778467 XD-1431 Fix review comments
* 19037db XD-1431 - rename top level directory in dist from batch to hsqldb