Enable unguided/automated installation

It should be possible to install a new instance of Bitbucket Server without manually going through the setup process.

An option would be to provide a properties file that contains the admin user information, user directories configuration (e.g. LDAP, Crowd or JIRA), database and the license information so that the setup process happen automatically.

Together with BSERV-3089 it should be possible to:

• Treat the downloaded artifact as being immutable with all the necessary changes defined outside of the installation directory
• Download Bitbucket Server and set it up using configuration management tools (e.g. Puppet, Chef, Salt, Ansible) that don't require a human to go through the setup process

Notes

The database can be defined as described in the comment below