v2.12-rc: Add support for environment variables and pre-compiled binaries

This update comes with two major changes:

1. It allows you to use environment variables to change parameters (such as port and path to activation file folder), which can be useful if you plan to run the license server as a service and do not want to compile a new version of the server for each client.
2. We provide pre-compiled binaries with default values, that can be overridden with a configuration file or environment variables.