SwIPC .id reference docs

[roblabla]

The format should be fully documented, especially the syntax and the different kind of data types.

[misson20000]

I wrote a draft of this a while ago. I'll look for it in a bit.

[roblabla]

This is a draft that was written by @daanhenke and I a while ago when I was thinking of breaking the format and changing things around a bit: https://gist.github.com/roblabla/f175994491a1f99c7031b4e244851570

It differs from the current format in several ways:

• buffers are totally different, much closer to switchbrew-style
• Array is a raw type instead of a buffer type
• khandle
• introduction of enums.
• namespaces.

Furthermore, the format for interfaces is incomplete.

[misson20000]

Addressed in #42.

I strongly feel that we should keep buffer similar to the way that it is.