Globals and nil, true, false

[smarr]

There's a question of priority for handling globals, and whether SOM has any names that are special.

nil, true, and false are very basic literals, and allowing them to be changed with System>>global:put: would be consistent with allowing Object>>become: on any object, but seems unnecessary cannon to shoot ones foot off.

Thus, my current preference is to have them simple keyword-like names, which are bound to the expected object.

Other globals, including system, classes names, etc, should be just globals that can be updated.

As discussed here:
softdevteam/yksom#90 (comment)

One could argue that this is an unnecessary complication, and there should not be any special handling of nil, true, and false, because it introduces a new concept, and needs an extra step in parser/implementations, and simply because it is inconsistent.
Still, I am currently leaning towards handling them special to match with what I assume a standard expectation is.