Feature: saved configuration

[mcg1969]

As ae5-tools gets more and more complex, there likely will arise a greater number of configuration options, some of which may benefit from having saved defaults. This is a call for someone to deliver a mechanism for saving configuration values to disk.

Let's talk about hostname for a moment. This typically feels like it has a saved defaults because of how the latest accessed session is recovered. But it might nevertheless be useful for a default hostname to be hardcodable (is that a word)? For instance, if someone regularly interacts with serverA and occasionally interacts with serverB, it might be useful to nevertheless force serverA to be the default every time, even if the last command was executed on serverB.

For username and admin_username: If a saved config mechanism saves these, they should likely be done on a per-host basis.

Some options may only be relevant to certain commands. I wonder if there is a convenient mechanism for specifying defaults those. Perhaps some sort of tree mechanism; e.g., project.list.format.?