Add tooltips for disabled menu items and buttons

[just-be-dev]

There are cases when we disable items in menus when the action is invalid in the current context. For example, you can't change a disk if it's attached to a running instance. We try to give context in the view that hopefully hints to why something is grayed out, but more explicit feedback would be helpful.

There's a strong argument that this would be an accessibility win too. As a sighted user, it's easy to glance at the bottom of a page and see a message saying certain things are disabled because of the state of the instance or something. Unless we use an announce or somehow add that messaging at a higher level in the accessible flow (which we likely should still do), it's possible that a user could get to the action before actually having the reason for its disabled state being announced. Having this extra context would mean that the button/item is announced as disabled along with context of why its disabled.

[just-be-dev]

In #1293 the ability to add a message about why something was disabled was added along with a few implemented examples. Now all we need to do is expand the coverage.

[david-crespo]

MVP because it's so easy and such a usability win.

[david-crespo]

We're using this in a few places. If we want it in particular places we can make issues or just do it.