It would be pretty cool if we could have tab auto-completion, similar to git's interface (as an example of something that has several subcommands). I would be interested in trying to start it at least for the Fish shell. This would probably only work for the Linux, *BSD and Mac environments, but I think it would make life much easier there.

Things to be supported:

• Tab completion for commands like lib and core
• Tab completion for the names of the options that can be passed, like --fqbn
• Tab completion for the board names and options and for target names when installing cores, for example (possibly hard to implement, would require parsing some stuff as well)