Improve CLI performance by serializing pregenerating data at build time that can deserialized during runtime

The way CLI support works is that each time the Main method is invoked, Simple Java Mail builds up the entire CLI command tree that can be invoked. This is a time consuming action and delays and command line execution by many seconds.

Instead, it would be great if we could generate it before each release, serialize the result to a file and deserialize that instead each time. That would make CLI commands execute near instantly.