Distributed execution context

[inducer]

• I'm not at all sure whether this should live in arraycontext, but I also don't know of a better place. It's clearly related.
• Names?
• Interfaces? So far, this is a weak mockup of what might be needed to unify what grudge needs from eager and lazy

cc @ZwFink @matthiasdiener @sll2 @lukeolson

[ZwFink]

Can you provide a little more context for how this DistributedExecutionContext would be used, and in what ways it would interact with the existing communication code in, e.g., meshmode? Is this intended to hide communication details of lazy execution?

[inducer]

Is this intended to hide communication details of lazy execution?

As discussed in the meeting today, yes, that's exactly the objective.